HUF - SUCESSION AFTER DEATH AND IT RETURN FILLING

Dear Sir, An huf was formed in the name of my father and grand father. Both of them have expired and as i am the only son now i am the karta of the huf left by my father and grand father. I had a querry regarding the pan card and pan number which was originally allotted to Huf in the name of my father and grand father. But as know both of them are no more and i have to file the incometax returns can you guide me weather i have to apply for a new pan card or send the same pan card to IT dept for change of name. What will be the process for the same. I am the karta of Huf know and i have my mother, my wife my son and daughter. I do have a married sister as well. will there be any share in property rental income of my sister. Please guide. Regards........