Makes perfect sense to me:
Infants as young as 18 months show altruistic behaviour, suggesting humans have a natural tendency to be helpful, German researchers have discovered….
…Many scientists have argued that altruism is a uniquely human function, hard-wired into our brains. The latest study suggests it is a strong human trait, perhaps present more than six million years ago in the common ancestor of chimpanzees and humans.
And the younger you are, the less chance you have for older human primates (i.e. adults…) to have talked you out of one of the behaviors that probably contributed to the survival of our species.