confused

My mother loaned my sister money for different reasons.My sister signed a letter stating if loan was not paid back then it would come out of her inheritance when mother passed.She never paid loan back and we took out loan from her share when mother's home was sold,she now say's she is intitled to 1/4 of the loan.If she never paid it in to estate would she be intitled to this back.

That amount owing is a receivable of the estate so it does have to be paid yes--you can take it from her funds.