I'll be honest, I think I'll need to get some full on financial advice for this but I'm not sure of the questions to ask if I do 
My DF sadly died a few years ago, and he left his half of the mortgage free family home to me and my 2 siblings. My DM had the other half and carried on living there. Therefore all 4 of us were named for Land Registry and we went to a solicitor who sorted it all out. Great.
DM is now moving. We want to use our half of the money to help buy her a house, which she will live in for the foreseeable future. DM is also using her money but her half of the family home isn't sufficient to buy the house she wants so we are contributing.
Are we able to loan DM the money interest free without it having any IHT complications? I am guessing we would put a charge on the house so that our loan is repaid in the horrible event of anything happening to DM.
I'm just aware that how we do it may have some Inheritance Tax complications inadvertently. DM's house will be over the IHT limit.
If anyone has any thoughts I'd be very grateful.