Is this scenario possible?

My mother, who currently lives in the family home, will shortly be
moving into a granny flat at my sisters house, Mum owns the home and
both my sister & I have mortgages on our homes.

As we don't want to sell the house is it possible to transfer the
owner****p of mums house into our (sister & I) names and mortgage that
house to pay off our mortgages and rent out mums house and treat it as
an investment property?

Thanks