Which is more deserving of a donation: completing the construction of an uncle's house or building a minaret for the mosque?

Assisting a maternal uncle is better than assisting in building a minaret for a mosque, because building a minaret is not an obligatory act, whereas assisting relatives combines kinship ties with charity. This is based on the Prophet, peace and blessings be upon him, who said: "Charity given to a poor person is charity, and to a relative it is two: charity and strengthening kinship ties."