Who survived in Mangal Pandey's family?
We don't know that. There is no authenticated evidence and no one can claim to be the descendant of Mangal Pandey.
Don't you fear controversies can bog down this historical film?
No Indian should feel that way. According to me, Mangal Pandey belongs to every Indian. He is a concept; he is beyond a human being.
I don't feel there is an issue. The writers of the film have written about Mangal Pandey the way Indians perceive him. So I don't think there will be any controversy with this film.