Can one every pay one's parents back in full?

Grandpa's taken ill. He's paralysed down one side. Mom's going to visit him this weekend. I've got her tickets booked. I miss him. I need do go down and see him sometime too. Probably after she is back.

Makes me wonder if one can ever repay one's parents back in full. I would think 'no'. No matter what one does for one's parents, one can never match the sacrifices they made for you, nor their love for you. The least one can do is to pass on all that love to and make all those sacrifices for one's offspring. You will never get it back from them in full. It can only be passed on down. Its a one-way traffic, but worth it.