Is it permissible for male children to enter the state of Ihram for Umrah in their sewn garments during the cold winter, for fear of them falling ill, while desiring to include them in the reward of Umrah?

Children must be stripped of sewn garments when entering into ihram, just like adults. They can be protected from the cold with thick ihram garments. However, if this type of garment is unavailable, and there is no other way to protect them from the cold except by having them enter ihram in their regular clothes, then it is permissible. In any case, if they are not stripped of their clothes and enter ihram while wearing them, a fidyah (expiatory payment) becomes obligatory, and it must be paid from the wealth of the person who put them into ihram.