@xmasbaby0 wrote:
@Opus 17 We do not know if the "ex" is an ex- spouse or an ex-girlfriend.
Even if the two adults were never married, the taxpayer here can claim the child as a qualifying relative dependent for any year where the child lived in their home or household for the entire year (all 365 nights), as long as they also paid more than half the child's support. Permission from the biological parent is not required. (This is a $500 credit). It would depend on the exact dates, "a year and a half" is too vague for this discussion.
Also, depending on when the child turned 17, and depending on whether "ex" means unmarried partner or spouse, the child might be worth a $2000 child tax credit, at least for 2022.
