How do I keep a family member in place when we need to sell?

[Aric Yuji Harris]

I have a situation in Petaluma and I wanted to know if anyone had any ideas as to how we might be able to solve this to everyone's satisfaction. 

There is that a family member is living in a detached carriage house on her grandmother's property.  She took care of her grandmother for some time before she passed feels attached to the property.

My grandmother though left a trust behind to distribute her property to her descendants with a little extra for that family member. That family member convinced her mother, the previous trustee, to let her stay in the property until she found a new place.

15 years later and over $300K of her personal funds sunk into the carriage house later and she is still there in a remodeled carriage house.
She doesn't want to move and is now co-trustee with another family member that does want to liquidate the house and distribute the assets.

Is there some way to satisfy both parties? We tried looking into buying out the other members but the percentages were so high that she would end up losing the house anyway from the monthly fees.

I am not sure how to proceed as I've mostly just dealt with simple turn-key properties or simple lending.  Is there a creative solution?  Any advice would be appreciated.

Thank you.