Claim on Father's Property

Dear Sir, We are a Christian Family. My father was a retired Central Government Employee. He purchased a land in his name & has a registered document and built a house with his savings. He left behind a widow(our mother) & four children { 2 son's & 2 daughter's }.. Elder daughter is still not married & is the guardian of elder son who is mentally retarded. They both stay with our mother. Younger son was married (No dowry) in Feb 2006 and has two daughters ( one born in 2007 & the other born in 2010). Our father died in November 2006. After that, younger daughter was married in Oct 2014 (She was given 3 lakhs in dowry during marriage) and has no kids till now. Please suggest the procedure if it has to be partitioned, how much share will each of the living heir will get legally without any dispute. And also, if mother wants to transfer the property (which is in my father's name still) in any of the daughter's name without the consent of other children, will such transfer is valid / not. For your reference, property is in Andhra Pradesh.