Covid-19 re-infections in kids under 12 years old?

Question for moms and dads out there with kids under 12 years old: Have any of your kids been constantly sick for a good part of the summer? I have twin 10-year-old girls, and both have had confirmed cases of Covid-19 over the summer. They are too young for the vaccine at this time. They had Covid about a month ago and recovered, and now they are having the same symptoms. I've had to keep them home from school today. I ask this because they used to *rarely* get sick – like once in a blue moon – and since early July 2021, they seem to be feverish all the time (99F to 100F usually, though it's been as high as 103.5F at the worst) with cold/flu symptoms. I'm just trying to get some insight from other families dealing with this. FYI: My husband and I are in our 50s, and we've both been fully vaccinated since May 2021. That said, my husband and I also had moderate positive cases of Covid-19 about 18 days ago. He and I were both treated and got over it completely. It just seems to be coming back again and again! I clean, disinfect, and we are vigilant about washing our hands. I wonder if this is going to be how it is for a while?? Very disheartening and frustrating!