Does custody of children return to the divorced mother if she marries and then divorces again?

The mother has a greater right to custody of the child, provided she does not remarry. If she remarries, her right to custody is forfeited by consensus of the scholars.

If the wife is divorced by her second husband, jurists differ on the return of her right to custody: The Shafi'i and Hanbali schools: Custody returns to her, whether the divorce is irrevocable (ba'in) or revocable (raj'i), because the impediment has ceased. The Hanafi school: Custody returns only with an irrevocable divorce (firqah ba'inah). The Maliki school: Custody does not return to her after the divorce.

In summary, the majority of scholars hold that custody returns to the mother if she is divorced by her second husband.