It's easy to check your children with questions about your ex-wife when they come for visits. He or she is one of the two things you have in common, and it is natural that you are interested in his life. However, there are things that you should not ask when you talk to your children, because you may cause them a lot of harm and confusion.
First of all, if you hate your ex-husband, your kids won't need to know why. They already know that you do not agree with other parents. After all, you no longer live with them, and if you cooperate with your other father, you will still share the space.
Do not discuss child support. Your children do not know if you pay too much. They can't do anything about the fact that the payments barely leave you enough to survive. They do not know what their mother spends on money, and they should not. If you are dissatisfied with making payments to them, you only embarrass them about a situation they have not created, and you cannot do anything.
There are safe topics that you can mention about the other parent. It is not intrusive to ask about their health, and if they have had a pleasant time on their leave. However, do not expect your children to report the love life of your ex-wife. Even if they knew that she was sleeping with a new man, or that he had just started dating a neighbor next door, asking your children questions was unfair. At best, they betray other parents, and encourage them to do so. At least, you will most likely get inaccurate information.
Children want to love both of you. It is difficult for them to do this when they realize that it is clear that each of you wants to harm the other. They are unprotected against attempts to trick information from them. Even if they know that they betray the trust of the other parent by spilling information, they will do so because they are afraid of losing your consent. This is a very uncomfortable situation, and in the end they will understand what you are doing and lose respect for you. Do they have a great interest. Keep your questions on topics such as school and activities, and make your children the kids they can. They may not be able to tolerate your ex-wife now, but when they grow up, they will be grateful. After all, they don't set the rules, but they know whether they're fair or not.