The problem is, it's all very well saying 'I'll share the money with you!' but then life changes, priorities change, and she probably thinks the money will come in handy for something they have planned, maybe home improvements etc.
And ultimately, it's your great uncle's choice where the money goes.
My great uncle (what is it about great uncles?!) told me he wanted to change his will to leave everything to me - then died a week later, two days before his solicitor came round to go through the paperwork of changing things.
I then had to watch my gran inherit 120k (she didn't know she was named in the will so she wouldn't have known any different if it'd been changed in my favour) when they were already well off and I had nothing to my name whatsoever, knowing that if my uncle had died just a few days later my life would be completely different right now.
So I had all that, the heartbreak of losing my uncle - who I was incredibly close to - and other life stresses at the time .. and I couldn't say one single word to anyone about it, as I knew it'd cause massive problems within the family.
So, Mumsnet, you're the first people I've ever told about that haha.