there is an exception for your parent as to claiming as a dependent
You can include medical expenses you paid for an individual that would have been your dependent except that:
1. He or she received gross income of $4,300 or more in 2021;
2. He or she filed a joint return for 2021; or
3. You, or your spouse if filing jointly, could be claimed as a dependent on someone else's 2020 return.
thus it would seem the only test you have to meet is providing over 1/2 the parent's support
