I am married to a man with 2 children. His ex-wife and him…

At this point your spouse has what is called "de facto" custody. This means that he has decision making powers despite the fact that there is no order because the law is that he is considered to have custody because the kids live with him full-time.

If the matter went to Court should would get access but whether that would be over-night or even unsupervised would depend on the facts.

The Court will make it's decision based on what it considers to be in the best interests of the children.

If there are emotional/psychiatric issues and substance abuse this does not make the mother's position strong.

Her behaviour is also irratic and highly irresponsible. To rmoeve from the child from school and take him for a weekend, out of the blue, is highly disturbing.

Your spouse can say no, especially if he's concerned about the children's safety and that she will not bring them back.

It may be that they can come to some agreement about her having supervised access and then unsupervised during the day access until it becomes clear things are OK with her.

But, it may also be necessary for him to get an Order giving him custody and setting out what type of access she may have.

No.