I'm sorry for your loss.
In my state, we must document and send, in writing, anything withheld from the security deposit. You are NOT allowed to charge for normal wear and tear, so four years in the same apartment would constitute some serious wear and tear.
This may be different for an assisted living facility.
However, the tenant is required, per law, to leave a forwarding address, in writing with the landlord. Mine did not, but I didn't want to lose (as a landlord) on a technicality, so I sent the security deposit and form and all receipts certified mail to the house they rented from me and it was forwarded. I kept the proof that I mailed it.
In my state, it is triple damages to a tenant if the landlord doesn't follow the 30 days. That means tenant automatically gets security deposit x3 back. Case closed.
Of course, you are dealing with different situations... no "notice", were things in writing ? I've heard that many judges are pro-tenant, so it may be worth it to go to small claims court.
good luck.