Doubts

Hey ladies, I have a question I kind of know the answer: just ask or talk with him. But in this situation how would you bring the subject up?

So I heard my husband talking with his sister (in Spanish - I don’t understand everything) about him talking by messages with his ex girlfriend (take news of each other).

I am not a jealous person but I cannot say it doesn’t bother me lol

And I think he said something like he hasn’t told me because it’s « nothing » and he doesn’t want to worry me with something meanless.

How would you react?

Would you confront him and how?

Fyi I am his wife and mother of his children. I am talking about a relationship that happened before being with me.