Two mortgages on forclosing home, will second come after my equity on my primary home that I own out right or retirement money I have in the bank in forms of cd’s?

I have a first and second mortgage on my home. The first mortgage is in forclosure. What is the obligation of the second lender. Is he obligated to pay his portion of the second mortgage and then forclose and then recoop his money? Or does the home just go into forclosre and then go to auction if not brought current on time.
Is the second under any obligation to bring the loan current or is it there choice?