wills/probate--Life ins.$ and mortgage$

life ins. amount is $462K and Mortage balance is about 110K--he had taken out a second a short time ago--once funeral exp. attorney fees, taxes, debts of any kind, etc. etc. are all paid--it appears there will be no money to fund the trust--which is why the mother and the girlfriend are concerned about the house--the house was to revert to my son at the age of 40 when the trust was to be dissolved--but since there could very well not be a trust who gets any residual (if any), if the house has to be sold?

Far too complicated. It depends on who title to the house was in, who the beneficiaries are, what debts there were, and if there was any binding agreement that applies.