Luke 15:12

The portion. According to the Jewish law of inheritance, if there were but two sons, the elder would receive two portions, the younger the third of all movable property. A man might, during his lifetime, dispose of all his property by gift as he chose. If the share of younger children was to be diminished by gift or taken away, the disposition must be made by a person presumably near death. No one in good health could diminish, except by gift, the legal portion of a younger son. The younger son thus was entitled by law to his share, though he had not right to claim it during his father's lifetime. The request must be regarded as asking a favor (Edersheim).

Unto them. Even to the elder, who did not ask it.