Great question
What's make me happy, it's depend on time or desires.
Imagine you are far from your family and you meet them after so long, then family makes you happy
Imagine you are in a desert for a long time and searching for water and you got a cup of water, then water makes you happy.
Imagine you are in jail for long time and today you are going out of it, then freedom makes you happy.
Of course there is not only one thing which makes me happy.
So what's make me happy, is "When i get something when i need it most."
Thanks for a great question @good-karma