Do any of her half-siblings inherit from my mother, given that she has two daughters and no male siblings?

If a woman dies and leaves behind daughters and full-paternal brothers and sisters (from the father only), then the brothers and sisters inherit what remains of the inheritance after the daughters' share. Full-paternal brothers and sisters are only excluded by the father, or the male offspring of the deceased (son or son's son), or a full-sibling brother. Daughters do not exclude the deceased's full-paternal brothers and sisters, nor do the husband or wife exclude them.