@notahappybunny7
Firstly, I am so sorry for your loss, bereavement is terrible and I’m sure you miss your Mum very much. I hope you are surrounding yourself with good people, getting therapy if you need it and trying to decompress as much as you can.
On to the thread topic. With respect OP, it doesn’t matter that your Father is a vile person who fucked your mother over.
They were married for 40 years and he has been resident in the house for as long as she was.
Regards to the 50k inheritance - I am really surprised the solicitor didn’t advise a dead of variation to allow this to pass to you directly upon your grandparents death. This would have avoided the whole scenario.
Also you could have had ownership of the property with your parents retaining right of residence.
Where on earth did you get legal advise, this could all have been sorted out while your mother was alive.
The only thing that can be done now is to seek proper legal advice and attempt to reason with your father to avoid legal action.
If it were me I would let him remain resident until he becomes too unfit to stay, at which point you can seek power of attorney to take control of matters fully. Provided his other offspring don’t.
Re. Care: If the house is in your name and you have the cash too, then he is simply a relative you have let stay in your house. There could be a claim for deprivation of assets but would depend on your individual circumstances- get advice.
If he fights in court and gets some/all of the estate then that will be taken into account and have to go on costs. He will also have the choice about who to leave it to.
You can expect the collective bill for action, should he press for it, to be in the region of 80k. For you this would be a devastating loss. For him he probably isn’t worried as he would be 230k up from where he is currently after costs. He may get legal aid.. not sure.
I would avoid name calling or further inflaming the situation with him. Be calm and reasonable. Avoid court if you can because he does have a very solid claim on the estate.
See a good solicitor pronto.