Gift Deed Transfer of property


We are Hindu family of 4 brothers and 1 sister, all are married and staying separately in their own houses, I am the eldest and staying with father who owns the house. Now my father wants to gift his house to my youngest brother only. He is reluctant to divide in all equally. Does our brother needs to procure written consent from rest of the siblings? And can we challenge it later in the court of law?
Thanking you.