For one of our lessons about families, I used my bike wheel in an object lesson. The whole wheel represents a family, with the individual spokes being the members of the family. All of the spokes connect at the hub or center, which is the place that God should occupy in our families.
When all of the family members are connected to and close to God, they get closer to each other, just like the spokes. You could get a little more in-depth with your analogy, but that’s where I stopped with mine. I didn’t want things to get too complicated for the kids.
I got the idea for this analogy from this Youtube video, so you might want to check it out to see which direction you want to go with your object lesson.