The promise to adopt must be based on some legal consideration. The absolute surrender
of the child by the natural parent(s) or by the person or agency with legal custody
upon a promise by the adopting parents to adopt the child is such legal consideration.
However, if the contract to adopt was made some time after the child was placed in
the care of the adopting parents, it must be shown that the surrender was then made
absolute and permanent in exchange for the promise of the adopting parents to adopt