@tattedese - on the "proof' question, children live with their parents until there is proof to the contrary. What proof does Grandfather have? Any legal documents? Other agreements that indicate Baby is now to live with Grandfather?
Your actually have proof in that the birth certificate with your name on it. Is Baby's mother's name on your lease. The hospital bills are 'proof' that Baby was NOT living with Grandfather; temporarily not living at home is still permanently living at home.
I just don't see what issue you have for 2020 as Baby did not live with Grandfather in 2020 ; 2021 may be a different story if Baby lives with Mom more than six months of 2021.
