When my parents finally decided it was time to go into a Home my brother (who has always been the black sheep of the family to put it mildly!) decided he would move into a caravan in their back yard and care for both of them. This patently ridiculous situation would have meant him leaving his wife and teenage daughter. It would also have meant him actually DOING something for once in his life!!! Fortunately my sisters and I just refused to consider the option and he eventually backed down, but not before considerable ill feelings were expressed.
In one way we were fortunate because there were 3 of us to 1 of him, and as our sibling, we met on even terms. Also the peroposal did not involve the sale of assets or such.
You would be wise to get legal advice as others have suggested.
Perhaps you could suggest that your stepson move into your home for a trial period of 6 months, during which time you will relinquish the care of your husband (his father) entirely to him. If at the end of this period all 3 of you are truly happy with the arrangement
, you will consider selling your half of the house!!!!!
Alternatively, you could suggest your husbannd move in with his son for the six months, thereby giving you a break, and allowing your step son to see if full time care of his father is something he wishes to commit to long term.
I realise you wouldn't want to do either of the above but it might test your stepson's resolve if there was no immediate monetary gain for him!! I may be very mistrusting, but I feel sure your step son would very quickly find a way to put his father into care and displace you from your home, if you followed his suggestion.
These people in families who do nothing or next to nothing and then want to ride in on white chargers at the last minute are nothing but a hindrance to those of us who have done the "hard yards".
I hope you can find a solution that meets your needs as well as those of your husband and *&^%$%^&* to your stepson!
Thinking of you, Nell