Sister Claim Share in property after father giftdeed to his son

Dear Respected sir, 1)Recently 6 months back father was dead because if illness aged about 69Y. 2)my father got two marriages and lived with both of them until first wife dead nearly 15 years back. Then after that he was leaving with us. 3)1St wife has one elder son(40Y) and one daughter (36Y) both are married and having there own children 4)2nd wife as elder son as me and one dauhter. 5)First he will-deed his house to his 1st wife's daughter and again he cancelled it after wards with all legal procedure( cancellation registered) 6)then before my father died he wrote Gift deed(legally registered) his house to my name with two witness and one my mother and one near by neighbour. 7)In that house 1St wife daughter's family living as tenant by paying 5000 monthly rent.they paid up to 2013 Jan only. 8) because of my father's love towards his daughter he couldn't do anything but sent one notice to pay rent or vacate the house resently before he died. 9) In replay Btother in law agreed of paying money has rent But said that money is controversy( not explained how) 10) Now that property is my father own earned but not any ansisters. and all the papers and All the property Documents are with me only they don't have any kind of papers.. 11) they are saying that for registration of gift-deed we should have four witness, two from my side and two from 1st wife side other wise the deed will not come in act is it true?. ----------so sir kindly explain the situation and give your invaluable suggestion what to do and how to proceed to get that house. Thanking you, Kannamma Nayudu. Hyderabad,Telangana, Pin-500003.