If Mom's house is in a Medicaid trust and needs repairs, am I allowed to pay for those repairs with her income?

You are in the first year? They look back five years. Please consult with an elder law attorney before you make an error.

I am not clear on how this was all set up. If she transferred the house into an irrevocable trust, and that was counted as a transfer subject to a penalty period if she applied for Medicaid within the next 5 years, then in that case any additional money she spends on the house at this point would be another gift, triggering a new 5-year lookback period for the amount of those additional payments. On the other hand, if family members paid house expenses/repairs out of their own pockets, that would not cause any Medicaid-related problems to your mother, since the trust now owns the house.