MN Child tax credit for decesed son

[Carl]

I'm sorry for your loss.

Basically, if your son qualified as your dependent for the previous tax year, then regardless of his date of passing in 2018, he qualifies as your dependent for the entire 2018 tax year. Weather you qualify for any dependent related credits or not will depend on what his age would have been on Dec 31 of the 2018 tax year. But in the Personal Info - Dependents section, make sure that you indicate your son lived with you "the whole year". That's important.