details on issue of waiver under article 1004, NCC as follows:
East, West, North and South are siblings and co-owners of an undivided property from their parents. East and West died without issue . North and South are both married with children. Before South died, North executed a generally waiver of all his shares from East and West in favor of South and limited his share only to 1/4 of the common property. May North do so to the prejudice of his compulsory heirs? If the waiver is valid, are there available remedies on part of his heirs?