الجواب وبالله التوفيق

• The responsibility of bringing the kids up after divorce is upon the mother until the boy child becomes seven years of age and the girl child until her puberty. However during this time the responsibility of the children’s expenses is upon the father. After the above mentioned age (or time period) the father has the right to take full custody of the kids. If during this time period the mother performs a new Nikah with someone else, then she loses the right to keep the children with her. After becoming adults (kids who have reached puberty), the kids have the right to choose which parent they want to live with.
• Whether the children live with the father or mother, neither parent has a right to stop the other parent from seeing the children. From a Shar‘ai standpoint, the responsibility of the expenses of adult children is not upon the father. If however the father does not support the kids during the above mentioned period (pre-puberty) then he will be liable for the sin associated with it.

والام والجدۃ ا حق بالغلام حتی یستغنی و قدر بسبع سنین    (کتاب النوازل بحوالہ فتاویٰ ھندیہ، ص 259، ج10

والحضا نۃ یسقط بنکاح غیر محرمۃ ای لصغیر    (کتاب النوازل، ص 260، ج10

ولا یملک احدھما ابطال  حق الولد من کونہ عند امہ قبل السبع و عند ابیہ بعدھا   (کتاب النوازل بحوالہ شامی، ص 259، ج10

والو لدمتی کان عند احد الابوین لا یمنع الاخر عن النظر الیہ وعن تعاھدہ   (کتاب النوازل، ص 264، بحوالہ تاتارخانیہ

واللہ اعلم بالصواب