Custody of children after divorce and purdah with step siblings

Q: I am divorced with two children (boy 9, daughter 7). My ex wife, has as I am led to believe, settled down perhaps made or not made nikah with the man I accused her with whilst we were married. I am not sure but I assume he is also divorced, he too has two kids of his own, also a daughter and a son I think maybe a year older than each of mine.

My first question is: What is the most authentic ruling regarding custody of children post divorce? Where and with whom and from what age should they reside with either mum or dad purely from what Shariah explains?

My second question and this is what haunts me: If tomorrow they all decide to move in together and lets say they are indeed married for purposes of this question, how does the mahram thing work? This man, is he mahram for my daughter firstly. Secondly, his children being exposed to my children, I fear abuse, bullying, sexual abuse(possibly! as a parent this thought lingers as they grow older and left alone), and my children being teased by his kids - that they only in that home because my ex wife married their father. Tomorrow if these step brothers or sisters or whatever they will be termed, if their natural father purchases or does something for my kids , they could get jealous or nasty towards my kids, maaf but all of these scenarios seem to be playing out, hence my questions. 

A:

1. In a case of separation or divorce, the custody of the children goes to the mother unless she remarries. If she remarries a non-mahram of the children, then she will lose the custody of the children. In the case of a boy, the mother has the right of custody till the age of seven and in the case of a girl, the mother has the right of custody till the age of nine. Thereafter the right of custody of the children moves over to the father.

2. If your ex wife has children from the person she has married, your children will be their uterine siblings on account of them sharing the same mother. Since they will be uterine siblings, they will be mahrams to each other and pardah will not be necessary amongst themselves. However, the children of her husband will not be your children's siblings.

And Allah Ta'ala (الله تعالى) knows best.

 

Answered by:

Mufti Zakaria Makada

Checked & Approved:

Mufti Ebrahim Salejee (Isipingo Beach)