Can my dad cancel gift deed done for younger son

Hi Team, I am writing this to get some ideas in respect to property law. We had two storey building. After my mother passed away my dad gifted one floor to my brother and another to me. The floor given to my brother is the same floor where my father used to stay for last 45 years. Suddenly after that my brother and his wife started misbehaving with my dad. Like they never give a single penny to my dad who is retired from business since last 20 years. They neither pay electricity bills nor the salary of the house maids etc. I live in Australia and bought my dad here for two months. Now I came to know that they thrown all my dad's garments to my floor and told he can't live to that floor anymore to the house maids. Now is there anyway to withdraw / cancel the gift deed by my dad from my brother. The deed is registered 8 months ago. Even then AC, geyser, wardrobe, bed all belongs to my dad. They have captured all of them. Please advice in which ground we can fight against this situation to make my brother understand and behave like a human.