Can my elderly mother be forced to sell her house

[Fastally]

My mothers partner has been diagnosed with Dimentia, left her and moved in with his son. My mother has been with her partner for over 20 years and cared for him post stroke for 14 years.

His family have now contacted my mother saying they wish to sell their house. My mother is close to 70 and does not wish to sell the house. The money from the house (50%) in its condition would not allow her to purchase another property.

We are worried his family can force a sale for any price (he has stated that he needs the money for holidays) and my mother would be homeless. The property is a joint tenancy but his family has stated they will contact the land registry and change this to common.

If anyone has experienced a similar situation the advice would be hugely appreciated.

Thanks

Fastday She lied about the severances, lied about probate, wouldn't accept that we didn't want to sell the house, as we and Dh's sibling both have our own homes, forced us into a Deed of Variation and IIP trust, that we had to pay for, by threatening us with High Court Action. She then reneged on an undertaking to meet the LR costs and claimed she had ' lost' the deeds, so that was another round of solicitors etc and yet more £k in legal bills.

We are NC, except via solicitors. This has been on going since 2011. I thought it had all gone quiet until we have been contacted via email by a firm that acts for her wanting our address. If we wanted her to have it, she would. As we do not, she doesn't.