How long will inheritance money affect benefits

My mum is due to inherit from my grandma. She is going to buy her own home with some of it and then do it up. She has promised my brother and I some money too, a few thousand.
If she gives us some, how long will it affect benefits? As it would be seen as getting rid of money?
She is on uc and pip.
She is going to tell them when she gets the money, but wondering if she gives some to us, she won't ever be able to claim again. Thanks