Is monthly spending on siblings and covering their living expenses and housing costs, due to the father's insufficient income to complete their studies, considered zakat for saved gold?

What is spent on brothers from zakat (definition) is not considered [as such] except under two conditions: that they are among those eligible to receive zakat, and that the intention of zakat is present when the expenditure is made. If it is paid without the intention of zakat, or if they are not eligible for it, then it is not considered zakat. Similarly, it is not permissible to disburse zakat to a student of knowledge except under specific conditions.