Thats Cheryl Mason. (well they found a different baby in the ending with Harry and Cybil in the fiesr game so thats, but she's technically supposed to be reincarnation im not a f**king silent hill lore nerd.)
Heather looks even less biological, and was technically a creation of the incubator. Cheryl was literally found on the side of the road, yes, but Heather is still adopted, even if she was literally made to be Harry's daughter.