Bring toys and props. During a family session I like to get all different types of combinations of people in photos, so I'll do the whole family then maybe just the children or just the parents and everything in between! So to keep you child's mood up in between photos, you can bring a toy for them to play with sometimes and it can be fun to get photos of them with a toy that means something to them. A favorite book, stuffed animal, ball, musical toy or whatever else that might enjoy is a great way to keep them happy and show some personality in their photos as well!
And my personal favorite, which I think is fun to do for any age family: make a fun day out of it! Play up the photo shoot as a special family day. You can do other activities after the shoot like go to the park, get ice cream, go out for lunch, or do some fun seasonal activity like picking apples or going to see Santa! The activities afterwards can be a good motivator to behave during the shoot.
I never want family photos sessions to be stressful for anyone. A calm, relaxed session is a great session, and hopefully with these tips it will help your whole family stay happy so I can create the perfect family photos for you!