Regret the way one treated one's parents after they have passed away.

 You never know what you've got till it's gone.

It is no use crying over spilled milk.

I wish I could have told him in the living years.

The world is like a grand staircase, some are going up and some are going down.

 Samuel Johnson

A home without books is a body without a soul.

 Marcus Tullius Cicero