ANY WILL can be contested by Legla heirs and other .................if other has an irrefutable interest in estate disposed by WILL..........................and a stranger can not..........
Resolve amicably if possible and the beneficiary may agree to give some share to by his/her sweet WILL...................to you and may be others....also.
In case of amicable family agreement, to rule out future altercations/litigations registered family agreement may be preferred.