Urgent legal advice - mother's dp dying and not divorced from wife of 40 years ago. Implications for will.

[Yellowbowlbanana]

My my mother's dp had a sudden diagnosis last week and is dying. We don't think he has that long and is deteriorating rapidly.
He spilt up from his wife over 40 years ago when she left him for another man (apparently, and we only have his side of things). He and my mother have been together for 25 years. The house is in joint names and their wills leave each other everything on event of one of them dying and then gets split 4 ways between the children. They have very little anyway and the house is still mortgaged.
Mum's DP wants them to get married which obviously requires him to get divorced first. I don't think we have time for this but I am worried about the implications of his ex-wife having claim to the house which would leave my mother destitute. She already stands to get his pension as it goes to his "spouse". The whole system seems so archaic.
Does anyone have any advice. We could probably get the divorce papers issued if that is required?
Thanks

Why isn't the pension solvable can name who you like?

Oh yes, definitely get a letter of wishes done at the very least.

It really depends on the terms on the pension. It ought to be possible for him to name your mum, but you need to know the exact terms.
Get advice direct from the pension provider.

@Springisspringing2

Why isn't the pension solvable can name who you like?

Some pensions are only payable to a spouse.

@Springisspringing2

Why isn't the pension solvable can name who you like?

You can't name who you like if it is a final salary scheme (other than for any lump sum benefit). Who the survivor's pension goes to depends on the scheme's rules - usually the legal spouse.