my friend mr A is interested in buying a agriculutural land of 1000 sq mt.the land was first in the name of one landlord mr X the land was in possesion of Mr. B and Mr C respectively they were both in the tenant names as husband and wife.but over a period of time father died and after his death the widow wife purchased it from the landlord on her name.she have 5 childrens 4 daughters and one son.the problem is that the son have illegally built a contruction in the agricultural land an is enjoying the possesion.now mother along with sisters want to sell the field as they are being cheated by the son.My client was interested in buying this field.Is it possible to buy from the mother and then ask the son to vacate the property,if so how?does the mother requires signature of the son and daughters ,does he enjoy any right of the property and if asked for partition for shares where does the son gets the share is it where he wants or is where mother gives please help?