ACCOUNTING OF JOINT HOME LOAN & TREATMENT IN ITR

I Have query regarding treatment of home loan...

Where.. Home Purchase is registered in mother name only,

While  Home loan is taken in joint where 1st borrower is son who actually pays entire installment , and 2nd co-borrower is mother for the loan purpose.

1. What will be accounting treatment of home purchase & home loan liabillity in the books of both in such case??
2. Who is eligible to get deduction in their ITR ??