I'm not a parent per se, but I routinely see my own childhood self in my nibling¹. It makes me always say a silent "I'm sorry, Mom" for all the same grief I caused her when I was a child.
I figure this is why parents (and moms, in particular, since historically they've been the one to rear children) are so revered: they put up with all that crap, and now we all feel guilty for it.