Seems every little thing is billed to someone else and trying to track it all is a pain in the rear. I ended up making a spreadsheet to track who billed what, what insurance paid each one, what insurance said we owed, and what they said we owed. And yes, sometimes there were discrepancies that I had to fight to get reconciled.

For what it's worth though, when we went thru everything with MIL, Medicare was amazing. Seems like she had a small deductible but everything else (other than the nursing home) was fully covered.