Mortgage By Deposit of Title Deeds

I apolosise for posting a irrelevent response by mistake. Excuse me for the same.

Loan can be given only by the bank and deposit of title deeds arises only between the bank and an individual, not between the individuals; so, a bond can be made for such deposit by including a clause about security of an immovable property ; that cannot be called as "mortgage by deposit of title deeds", as that is not between the bank & an  individual

Mother and father are the joint holders of a property. EQM is to be created for the security of educational loan of the property but one of the title holders i.e. the mother has expired and the procedure of change in title has not been instituted, now should the legal heirs have to sign the equitable mortgage document (Register) ?