Rory Delaney is a three-year-old who has not been out of diapers that long, but she already knows something about changing them. Her sister, Saorise, is a five-year-old kindergarten student who already knows what she wants to be when she grows up, a mom. Now, researchers at Rockefeller University say the inclination that both Rory and Saorise feel at such a young age to nurture and feed their baby dolls and play with items like strollers could be something they were born with, and something that will definitely impact their futures. In a study with mice, the researchers determined that a single gene exists that could be responsible for motivating mothers to protect, feed and raise their young.