Is it permissible to give zakat to one's father and siblings to help them with living expenses after the monthly income from the investor ceased, knowing that the original capital was not taken from the investor?

It is not permissible to give zakat to a poor father if his maintenance is obligatory upon the zakat payer, because by doing so, the zakat payer would be protecting his own money and absolving himself of the obligatory maintenance. However, if the father is not in need, then he is not eligible for zakat. But, if the father is poor and the zakat payer is unable to provide for his maintenance, then it is permissible to give him zakat according to many jurists. It is permissible to give zakat to poor siblings because their maintenance is not obligatory upon the zakat payer, especially if the father prevents the zakat payer from inheriting from them.