I"m afraid that's not how it works.  Absent an agreement to reimburse her for this expense, she is not entitled to it or to a greater share of the house for that matter.  While it seems unfair, that's the law.  All 4 of them jointly hold an ownership interest in the house and 1 co-owner cannot obtain a greater share than the other(s) without the written consent of the others.  She'll just have to look at the money that she paid as a form of rent.  Unless of course, her brothers want to do something different out of fairness.Note:  If your grandmother was in some way duped into making these payments, either intentionally or by mistake, then a court may elect to have your grandmother reimbursed for these payments by employing the equitable remedy of "unjust enrichment".  In other words, the other owners should not unjustly benefit from her paying the mortgage all of those years.  However, absent some sort of mistake or deceit on the part of her co-owners, such a remedy will not be applied.