Don't Say: "My kids."
When I began practicing family law, this is the very first thing that I remember my mentor (who has over 30 years of experience as both a family law attorney and more recently as a pro tem judge) telling me. To this day, I say it to nearly every client and internally cringe when I hear a client say this in court.
Here's why: When you say "MY kids," you have just turned them into an object, or worse, a possession. The judge is making decisions based on what he or she believes to be in the best interests of the children. You should be doing exactly the same thing. The judge is also interested in which parent is more likely to facilitate a relationship between the children and the other parent. When you say "MY kids," you've just shown that you don't really see the value of the children's relationship with the other parent. This simple turn of phrase can make a judge assume many things about you, whether they are true or not. That's why I remind my clients about this tip every time I hear them say "MY kids." Get in the practice of not saying this, because when you are in court, you will be nervous, and you will revert to whatever your habit is. Same goes for custody evaluations.
Do Say: "Our kids."
If you just can't bring yourself to say that, then try "the kids" or simply using their names. Let the other parent be the one to make the children sound like a possession to be fought over.