When you have a child with someone, statistics show that it doesn't always mean you will be with that person forever. For the benefit of the child, when two parents do go their separate ways, the parent who does not have the child all the time is typically expected to pay child support. The individual state determines how much you should pay according to your income, the child's needs, and how much time the child spends with you compared to the other parent. A common concern is how the child support you pay is being spent, which is only natural when you want to see the money go to the child.
1. Is it legal for the other parent to use child support to pay for housing?
If the other parent is using child support to help cover the costs of rent or a house payment, this is actually for the betterment of the child. Therefore, it is perfectly legal if the other parent uses a portion of what you pay to cover these costs. The only thing that could be a concern is if the money is being used in totality to cover housing and the child is doing without other important things. For example, if your ex moves into a luxury apartment but your child complains to you that they aren't getting enough food to eat, this could be a serious problem. If you're unsure if your ex is using child support correctly, discuss your concerns with a child support attorney.
2. Is it legal for child support to be used to support other children other than your own?
The lines here can get blurry, and it is because it is hard to differentiate support between the children in one household. If you are paying $1,000 per month for your child and your ex has two other children with someone else, it is only natural that the other children will benefit from that support in some way. For instance, if the custodial parent uses part of that $1,000 to pay the electricity bill because it is a basic need for your child, this is also going to benefit the other children in the house.
In most cases, there is no way to prove the other parent is doing anything wrong in these situations because technically, or legally, they aren't. The only way it would matter is if what you are paying is going for the betterment of the other children and your child's needs are being outright neglected.