Ok here it is...I've posted in relationships too - sorry if that is bad forum etiquette.
I am asking on behalf of a friend.
My friend, who lives outside the UK, has returned home to discover that her BIL has been physically and mentally abusing their MIL, he has had long term mental health problems but he seems to have seriously deteriorated - they had no idea as MIL said nothing. When they realised and it didn't take long they removed her from the home on the pretence of wanting to spend time with their dcs in their hotel room, but on returning back the next day things escalated quite badly and the Police were called - he was arrested and spent the day in jail.
The MIL and my friend are now staying in a hotel room, they are in contact with social service to arrange care - MIL is partially sighted and can’t live independently, she is incredibly frail and vulnerable, but things are moving slowly.
BIL has been sending incredibly aggressive emails - accusing my friend of ruining his life, taking away the only person he cares about - lots of burning in hell - extreme religious cult like views. Friend is scared that he knows where they live outside the UK - they are scared for their lives
I don’t know if anyone can help - we’re all out of our depth - it’s 5 days since this started and his anger is still poker hot, he’s determined to find his mother - they cannot easily stay in the UK beyond their planned holiday…. but they can’t leave her either.
The biggest fear at the moment is that he finds his mother and he travels to my friend’s country to seek revenge - they have asked Social service to help the BIL but they are not convinced he is ill enough to be sectioned.