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It is mid school holidays so I imagine there will be a few kids (Celebrity is not a line that attracts a lot of children though). Given your itinerary I would do each port by myself and not bother with shore excursions, but that is your choice.
I would not book tours on this trip as each port is so easy to do by yourself. Just my opinion.
If you are going in school holiday time the answer is probably yes and there is a chance out of that time as schools around the world have differing holiday times. As " Albert" says I wouldn't pre-book tours either but have a good idea of what you might like to do. Often it is easier and cheaper with four you to do it on your own or you may find others who are doing it alone and be able to join them or you may find that the children's entertainment supercedes some of your ideas, it's very good on Summit. .... Neil.
If you sign up for the Connections party you will find fellow travellers with children.