Yes we can but currently it does not include sibling marriages of convenience to avoid tax. I am awaiting an explanation of why it should
Because life partnerships exist between siblings.
How about mum marries son a dad son b all just to avoid tax….still ok with you ?
Yes. I know of a mother and son, both elderly, that are in a life partnership (they’ve been interdependent for 40+ years). On the death of the mother the son could get a tax bill and have to leave his home. I doubt the house is worth enough to be fair, but they should have the same protection as any other couple can gain through marriage.
My sister in law and husband lived with her father. I did suggest my sister in law divorce her husband so he could marry her father to avoid them getting taxed on inheriting the shared family home. She didn’t go for it. But what your suggesting is possible now and entirely reasonable.
In fact limiting marriages to couples is a bad idea. If you choose to live with your parents you should be able to form a four way marriage to gain the same benefits as a couple in a life partnership.