i remember hearing, that child development wise, kids only are capable of empathy, from about the age of 6 or 7. Not sure i agree with this 100%, as bilby has been empathetic (not in everything, but when other people get hurt for example) from a younger age.

Saying sorry is big to me, after being raised by parents who NEVER apologised for anything, and then having a partner who could NEVER say sorry, even if ten people saw him purposefully do something wrong, he would always make a joke about it, instead of apologising.