Therefore , in your case , you can become karta , but before that its better if you get an agreement signed among all HUF members stating that your father , owing to his age , is passing on kartship to you and that other members are agreeing to it.

Yes, a junior member can become Karta . You should also know a son can become father’ huf. Even a one male member is enough for HUF.As far as Income tax Act is concerned , there is not big impact for such change of guard since the income shall always be assessed in the status of HUF . The return can be signed by you. What you should do is to inform the A.O on plain paper that now you have become the Karta of the HUF and that you will be filing returns thereafter.

As far as your son is concerned , he is certainly part of HUF and you can inform the I T Authorities on your own volition, and keep a record of that.