Say for simplicity the house is worth €500K and is to be divided equally between 5 siblings. House sells and each sibling ends up with €100K.
However, Mary, has a right of residency until she dies, she is 40 and can potentially live until 80. She needs to give up her right of residency for the house to sell. A value of 25% of the house value is put on this. The house is sold. Mary gets €125K as her right of residency. There is €375K left, each sibling including Mary gets €75K.
So you want to live in the house, then you buy it for €500K, you get €75K from the inheritance and take out a loan for €425K.
The executor must make the decisions, and take action. It should not matter to him what the other siblings would like or not like, it is what is in the will that m. The right of Mary to live in the house must be recognised as a cost to the estate.
If I was him I would do the following.
Charge you and your husband rent including back rent for the last 4 years at market value, less vouched costs of any jointly agreed upkeep or improvements to the house.
Value the house and come to an agreed value.
Agree with Mary’s legal representatives the % value of the house her right of residence is worth.
Offer to sell the house to you for the agreed value (maybe 3 valuations and take the average).
If you can’t buy at the price or raise a mortgage, sell the house on the open market.
Distribute the estate, less costs and taxes.