If you are looking for a thank you when you have done something for someone, forget it. The motivation is all off.
Do something without expecting something in return. Then you won't be disappointed.
A thank you would be nice especially if gone the last mile for someone.
The author is not asking for bended knee gratitude just a little common politeness and respect.
It is nice to see someone so young learning the value of thank you
You feel disappointed?............ because you feel a need to be appreciated?