Researchers at Yale stuck babies between 6 and 10 months old in front of a puppet show, a morality tale featuring anthropomorphic geometric shapes, which sounds like the shittiest puppet show ever. Basically it boiled down to a yellow triangle helping a red ball up a hill, while a blue square tried to push the red ball back down. All of these shapes had eyes, if that helps with your mental picture. The important part is that when given a choice on which shapes they preferred, 80 percent of the babies reached for the helper shape, as if to say "You are the best and I want you" (or possibly "You are the one I am going to eat because I too am evil," but probably that first one).
If you think that was just a coincidence (like maybe the helper shape was also shaped like a boob), they've done multiple versions of the study -- for instance, babies as young as 8 months agree that justice should be rewarded and evil should be punished. That study was again conducted with puppets (the universal language of babies), and in this one a bad puppet was either rewarded or punished as the babies watched. This time, the babies picked the punisher as their favorite. Not the victim or the bad guy, but the one who administered justice.
Dynamic Graphics Group/Dynamic Graphics
A baby who doesn't love Frank Castle isn't a baby we'd want to keep anyway.