I have a kid who is now 17, but was not when filed in 2018. Does that count or no.

I also have a kid who just turned 20. He won't qualify. He made a little money in 2018, but not much and didn't file and I did list him as a dependent. He made nothing in 2019 and nothing so far this year (mission). When he gets home this year and starts working would he get some when he starts working and files this year or not?