Sheikh Mûhammad al-Ghâmidî, professor at King Khâlid University
The mother is entitled to the custody of her children unless she gets remarried. Our Prophet (peace be upon him) told a woman: “You are more worthy for the custody of your child unless you get married” [Musnad Ahmad and Mustadrak al-Hâkim]
If the mother gets remarried and custody becomes an issue, then the right of custody transfers to her mother, then to the baby’s father, then to his mother, then to his father’s father, then to the sisters of the child, then to the child’s aunts.
Such is the order of priority for guardians. However, in some cases, custody will be awarded in consideration of the best interest of the child without any consideration to the above system. In this case, the child may stay with his mother even if she gets married, but all this can only be decided by the judge.
If the uncle of your daughters insists on being the guardian of your daughters, you must consult the proper Islamic judge in your area. The same thing applies to the guardianship of their properties. The whole matter is up to the judge.
Source: Islam Today