Wales - can you co-own a house and get housing benefit?

grandma wants to pass the deeds to her house to my dad and aunt before she gets too old (she’s terrified she’ll get dementia even though there’s no signs there yet). We all know (and have always known) that the house is going to my aunt as she’s lived there almost her entire life and has been caring for my grandma for years. The understanding is that when my aunt passes, if my dad is still alive the house goes to him, and then after that all us grandkids can fight over it.

The question at the moment is, my dad currently rents a house and gets housing benefit element of UC. If his name is on the deeds of another house, will that money stop?