Short Answer
               M~ is the biological mother of M2~, who has a pending claim for child insurance benefits
                  based upon the record of R~, M~’s husband. Both M~ and R~ report that M~2s’ biological
                  father is J~. J~ was also listed as the father on M2s’ birth certificate and M2~ shares
                  his last name. You have asked whether M2~ qualifies as R~’s child, as determined in
                  Illinois state law for intestate inheritance. For the reasons discussed below, we
                  believe that M2~n is not R~’s child, as that term is used for child insurance benefits
                  purposes.
               
               Background
               M~ is the biological mother of M2~, who was born on January XX, 2010. She filed for
                  child insurance benefits on behalf of M2~ on November XX, 2014. The Child benefits
                  claim was based upon the record of R~, M~’s husband. M~ has lived in Illinois with
                  R~ and M~ since before the application date. R~ and M~ have been married since December
                  XX, 1990. Both M~ and R~ report that M2~s’ biological father is J~. J~ was also listed
                  as the father on M2s’ birth certificate and both share the same last name. R~ has
                  not adopted M2~.
               
               Discussion
               An individual is eligible for benefits as an insured’s natural child if the individual
                  could inherit the insured’s personal property as his or her natural child under State
                  intestate inheritance laws. 20 C.F.R. § 404.355(a); 42 U.S.C. § 416(h)(2). The relevant
                  State is the State in which the insured is domiciled at the time of application, or
                  the State in which the insured was domiciled at the time of the insured’s death. 42
                  U.S.C. § 416(h)(2)(A). We apply the State law in effect at the time of our final decision
                  on the application for benefits. 20 C.F.R. § 404.355(b)(3). If a claimant does not
                  qualify as a child of the insured under that version of State law, we look at all
                  versions of State law in effect from the first month a claimant could be entitled
                  to benefits until the time of our final decision, applying the version of State law
                  most beneficial to a claimant. Id.
               
               We look to Illinois law regarding intestate succession because there is no question
                  that R~, the insured, is domiciled in Illinois. Illinois establishes separate intestate
                  distribution for children born out of wedlock. 755 ILCS 5/2-2. A child born out of
                  wedlock is defined as “a child whose parents were not married to each other at the
                  time of [the child’s] birth.” People of the State of Illinois, ex rel. Raines v. Biggs, 481 N.E.2d 899, 901 (Ill. App. Ct. 1985); see also Sturdy v. Sturdy, 214 N.E. 2d 607, 609 (Ill. App. Ct. 1966). Based on the evidence discussed below,
                  we believe that M2~ was born out of wedlock, because evidence indicates that his biological
                  father and mother were not married to each other. A child born out of wedlock is heir
                  of his mother and of any maternal ancestor and of any person from whom his mother
                  might have inherited, if living. 755 ILCS 5/2-2(h). A child born out of wedlock can
                  also inherit from a father who has acknowledged paternity, or if the father has been
                  adjudged the father of the child born out of wedlock. 755 ILCS 5/2-2(h). In all other
                  cases, inheritance occurs when paternity is proven by clear and convincing evidence.
                  Id. Here, the operative question is whether R~’s paternity would be established by clear
                  and convincing evidence, because there is no indication that R~ was adjudged the father
                  or acknowledged the paternity of M2~.
               
               In determining what counts as clear and convincing evidence of paternity, the Illinois
                  Parentage Act has established presumptions of paternity that are applicable. In re Estate of Poole, 799 N.E.2d 250, 257 (Ill. 2003). The Illinois Parentage Act applies in any civil
                  action when parentage is at issue, even if not brought under the Illinois Parentage
                  Act. 750 ILCS 45/9(a); In re Estate of Poole, 799 N.E.2d at 256 (applying definitions from the Illinois Parentage Act in a probate
                  context). This inquiry requires analyzing both the prior version of the Illinois Parentage
                  Act of 1984, which was in effect from 2007 until December 31, 2015 and the current
                  Illinois Parentage Act of 2015, which took effect on January 1, 2016. It is necessary
                  to look at both laws in order to determine which of the two laws, if any, is most
                  favorable to the current claim for child insurance benefits on R~’s record. 20 C.F.R.
                  § 404.355(b)(3).
               
               Illinois Parentage Act of 1984
               Under the Illinois Parentage Act of 1984, Illinois provided that a man is presumed
                  to be the natural father of a child if he and the child’s natural mother are or have
                  been married to each other, even though the marriage is or could be declared invalid,
                  and the child is born or conceived during such marriage. 750 ILCS 45/5(a)(1). A man
                  is also presumed to be the natural father of a child if after the child’s birth, he
                  and the child’s natural mother married each other, even though the marriage is or
                  could be declared invalid, and he is named, with his written consent, as the child’s
                  father on the child’s birth certificate. 750 ILCS 45/5(a)(2). Alternatively, a man
                  is also presumed to be the natural father if he and the child’s natural mother have
                  signed an acknowledgement of paternity, or if the natural father is someone other
                  than one presumed to be the father, an acknowledgement of parentage and denial of
                  paternity in accordance with Section 12 of the Vital Records Act. 750 ILCS 45/5(a)(3),
                  (a)(4).
               
               A presumption of paternity based upon either 750 ILCS 45/5(a)(1) or (a)(2) can be
                  rebutted only by clear and convincing evidence. 750 ILCS 45/5(b). A presumption under
                  750 ILCS 45/5(a)(3) or (a)(4) is conclusive unless the acknowledgement of parentage
                  is rescinded under rules described in 750 ILCS 45/5(b). “A rebuttable presumption
                  is one that ‘may be overcome by the introduction of contrary evidence’ (Black's Law
                  Dictionary 1224 (8th ed.2004)), while a conclusive presumption is one that ‘cannot
                  be overcome by any additional evidence or argument.’ Black's Law Dictionary 1223 (8th
                  ed.2004) (cited in People ex rel. Dept. of Public Aid v. Smith, 818 N.E.2d 1204, 1213 (Ill. 2004)). The reason for this distinction flows from the
                  different degree of involvement of the presumed father. “A man who voluntarily acknowledges
                  paternity signs an acknowledgment form advising him of his rights and specifically
                  informing him that he is accepting the responsibility of being a parent to the child,
                  that he has a right to genetic testing, and that he is waiving that right by signing
                  the voluntary acknowledgment. Thus, a presumed father who signs a voluntary acknowledgment
                  is in an entirely different position from a man who simply assumes he is the child's
                  father because of his marriage to the child's mother.” People ex rel. Dept. of Public Aid, 818 N.E.2d at 1213-1214.
               
               Applying these principles, there was a rebuttable presumption that R~ is the father
                  of M2~ under the Illinois Parentage Act of 1984, because M2~ was born during R~’s
                  marriage to M~. However, we believe that J~ benefits from a conclusive presumption
                  that M2~ is his child.[1] J~ signed M~’s birth certificate. 410 ILCS 532/12 sets guidelines for issuing birth
                  certificates. If the mother was married at the time of conception or birth and the
                  presumed father (that is the mother’s husband) is not the biological father of the
                  child, the name of the biological father shall be entered on the child’s birth certificate
                  only if, in accordance with subsection (5), (i) the mother and the person to be named
                  as the father have signed an acknowledgement of parentage and (ii) the mother and
                  presumed father have signed a denial of paternity. 410 ILCS 532/12(4).
               
               Because J~’s name was on the birth certificate we believe that J~ also signed an acknowledgement
                  of parentage and that M~ and R~ signed a denial of R~’s paternity. We recommend that
                  you request these documents to confirm that this occurred, as well as confirm that
                  the acknowledgement of parentage was never rescinded. Assuming that these documents
                  exist, they are sufficient to create a conclusive presumption of paternity of J~ under
                  750 ILCS 45/5(a)(4). We believe that the same evidence that establishes the conclusive
                  presumption of J~ is clear and convincing evidence that overcomes the rebuttable presumption
                  of R~’s paternity.[2] See In re Estate of Olenick, 562 N.E.2d 293, 299 (Ill. App. Ct. 1990) (holding that an appropriately authenticated
                  acknowledgement of parentage, under a prior amendment of the Illinois Parentage Act
                  of 1984, was clear and convincing evidence of paternity).
               
               Further, although not determinative, there is additional evidence in statements from
                  R~ and M~ that M2~ is the child of J~, as well as the fact that M2~ bears the same
                  surname as J~. As such, clear and convincing evidence rebuts the presumption of paternity
                  of R~ and establishes a conclusive presumption that J~ is the father of M2~ under
                  Illinois law. Thus, M2~ cannot inherit as R~’s child under intestate succession.
               
               Illinois Parentage Act of 2015
               The Illinois Parentage Act of 2015 has been in effect since January 1, 2016. Under
                  this law, the parent-child relationship is established between a man and a child if
                  there is: (1) an unrebutted presumption of parentage of the child under Section 204,
                  (2) an effective voluntary acknowledgement of paternity by the man under Article 3
                  of the Act, unless rescinded or successfully challenged, (3) an adjudication of the
                  man’s parentage, (4) the man adopted the child, or (5) a valid gestational surrogacy
                  contract. 750 ILCS 46/201(b).
               
               The law establishes a presumption of parentage in four circumstances. 750 ILCS 46/204.
                  Under the first circumstance, parentage is presumed where the person and the mother
                  of the child have entered into a marriage, civil union, or substantially similar legal
                  relationship, and the child is born to the mother during the marriage, civil union
                  or substantially similar relationship. 750 ILCS 46/204(a)(1). Presumptions may be
                  rebutted by clear and convincing evidence. 750 ILCS 46/206.
               
               Under the voluntary acknowledgement of paternity described in 750 ILCS 46/201(b)(2),
                  the effect of an acknowledgement of paternity is equivalent to an adjudication of
                  the parentage of a child and confers upon the acknowledged father all of the rights
                  and duties of a parent. 750 ILCS 46/305(a). Also, a valid denial by a presumed parent
                  filed with the Department of Healthcare and Family Services, as provided by law, in
                  conjunction with a voluntary acknowledgement, is equivalent to an adjudication of
                  the nonparentage of the presumed parent and discharges the presumed parent from all
                  rights and duties of a parent. 750 ILCS 46/305(c). An acknowledgement of paternity
                  with a valid denial by a presumed parent overcomes any presumption that a marital
                  spouse is a parent, because this is equivalent to an adjudication. 750 ILCS 46/305(c).
               
               Applying the Illinois Parentage Act of 2015, we believe that M2~ would not be found
                  to be R~’s child. R~ initially would be a presumed parent under 750 ILCS 46/204(a)(1).
                  However, assuming that J~ signed an acknowledgement of paternity of M2~ and that R~
                  denied parentage as discussed in the section above, this would be sufficient to overcome
                  the rebuttable presumption that R~ is the parent and establish a parent-child relationship
                  with J~ via 750 ILCS 46/201(b)(2), 46/305(a), (c). The Illinois Parentage Act of 2015
                  also clarifies that a child can have at most two parents. 750 ILCS 46/102. Thus, we
                  conclude J~ would be found to be the parent of M2~, not R~, and thus M2~ could not
                  inherit as the child of R~ for the purposes of intestate succession.
               
               CONCLUSION
               For the reasons discussed above, we believe that M2~ cannot receive child insurance
                  benefits on R~’s record, because M2~ cannot inherit as R~’s child under Illinois intestate
                  succession. We recommend that you request documentation that R~ signed a denial of
                  parentage and that J~ signed an acknowledgement of paternity, as discussed above.
               
               Kathryn Caldwell
               Acting Regional Chief Counsel, Region V
               By: Ryan Shafer
               Assistant Regional Counsel