All perfect praise be to Allah the Lord of the Worlds. May His peace and blessings be upon Prophet Mohammad and upon all his family and companions.
Undoubtedly, the sum-150 JDs-that you (Asker) have taken from your uncle is unlawful to you because you didn`t ask for his permission. In this regard, the Messenger of Allah (PBUH) says: "It isn`t permissible to take the wealth of a Muslim without his consent/permission." {Related by Ahmad, No. 5/72}.
It is incumbent upon you to return that sum to your uncle and ask him to forgive you because this is better and draws you closer to Allah`s forgiveness.
However, if you are worried that making such confession would make him hate you and severe kinship ties, then you could deposit that sum in his bank account without telling him, in addition to making sincere repentance to Allah and asking Him to forgive you. And Allah The Almighty Knows Best.