Parents are the life givers, you are a part of both (mom and dad) when it comes to sacrifice they make is not something to flaunt or show off but is an expression of love.
A man letting go off his dream car so that his daughter can get admission in the top school. A maid saved box of sweets which she got for her son .
These are small say to day sacrifices which every parent make to see the shine in the eyes of their kids.We may call it sacrifice but for parents its a gesture , a way to express love .
For them their happiness is in the happiness of their child so its not a sacrifice while its their way of being happy.Also sacrifice is an expression which one can not to do that easily an emotional bonding is required here and in a parent child relationship which is very strong.
Parents love is said to be a form of “Selfless” love therefore for them its not a sacrifice rather something natural and as a parents they expect it from themselves.
I hope I was able to guide you to get your answer.There are lot of questions like this which we face quite often and I know such questions bother us a lot and its good if we get the answers of these questions also One should not keep such matters inside.