You will need to look through all of the rules, but most likely it comes down to "Did the child provide over half of his own support?" Income does not matter; it is based on who paid for support.
https://www.irs.gov/publications/p501#en_US_2024_publink1000220886
https://apps.irs.gov/app/vita/content/globalmedia/teacher/worksheet_for_determining_support_4012.pdf
