My 1st question is whether all the children have their share in that or only daughters can claim their mother's ancestral property?
The properties in the hands of married women will be their own and exclusive property, over which nobody has any share or right including their daughters or sons or husband.
2) My father had earned some agriculture land and other property i.e.houses etc on his own.Certain part of the property he distributed among his children before his death and some he kept in his name.After his death my elder brother claimed/told me that our father had written all the property in his name as I was staying away for my job in another city .He had never shown the will to me.Now my elder brother is no more he died in 2007.After his death his 3 sons have captured /grabbed that property.Whenever i am trying to ask for the will they start fighting and claim that they have the will but never show it to me.
The act of grabbing away the entire intestate property by one brother based on an a fake or unfound will cannot be considered as valid in the eyes of law, if the brother is no more, then a partition suit may be filed seeking a legitimate share in it impleading the heirs of brother and others as defendants.
1) After my brother's death; who would have the right to the property (passed down by my father to him) - his scions/wife or his siblings?
If the property was duly transferred and registered on the deceased brother's name then only his legal heirs can claim ,if not then the property will devolve on all the legal heirs of your father.
(Que 2) can I or my children claim the right to our part of the property (If yes then what is the procedure) ?
If the property was not transferred properly and it was just like that grabbed illegally by the deceased brother, you have a claim in it as a legal heir to your father and can file a partition sit as stated above.
(Que 3) Can my siblings (immediate and cousins) and their children make a claim to this property. >
No, not during your life time.
(Que 4) My mother died in 1992 and father in 1994.I got retired in 2012. Is there a time limit by when i can make a claim to this property.?
No time limit for filing partition suit or claiming the property by partition. It can be claimed any time during life time.
(Que 5) Is there a way i can get all the details from RTI ?
What details, specify.
Finally without our consent can my brother's children/wife sell this property?
In the partition suit you have to file an interim application for injunction restraining the defendant from alienating the property till the disposal of the main suit.