Capital gain on inherited property

Dear Friends,

A person is inherited with property due to his fathers death, but there are 3 person who are sharing the property i.e mother, brother and sister. The query is that if the brother doesnt want the share of the property and allows his mother and sister to share the property equally then is hi liable to capital gain or not. There is no writen document of forgoing the share made.

Why wud he be liable to capital gain if there is no sale consideration at all...wud be a case of gift if deed is made...no tax on gifts..!!