Just know that everything is closed except for a few spots. Saturday and Monday are still difficult to find places to go to, but Sunday is definitely close to impossible to find something open.
This is all that I was able to find (updates will be made if anything else pops up on our radar):
Afi Cotroceni – shopping mall
It will be open from 14:00 to 22:00, what is open, I do not know but good luck.
Btrip – tip based tours
Old town tour that starts at 10:30 ( Link )
Afternoon tour (Communism vs Monarchy) that starts at 17:00 ( Link )
Pro tip: make a booking, as if there are not enough tourists the tour is not going to happen).
Beraria H – concert, fish festival and traditional dances
Sea food festival 12:00 – If you love fish this is your opportunity to eat (Link for booking a table)
Folk Dances 13:00 – You can enjoy drinks and food while being entertained by Romanian traditional dances (Link for booking a table)
Radu Almasan (Bosquito) 17:00 – Live acoustic music – the entrence is free
Hard Rock Cafe – Easter Eggs Hunt for kids
Find those pesky chocolate eggs between 13:00 – 15:00 at Hard Rock Cafe – the entrance is free ( Link to Reserve a Table )
T5 Social – Games Night
More information here: https://www.facebook.com/share/r/or5ykSAuXjhv3V1L/
Tips for what else you could do:
Or
Dracula's Guide to Romania 
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