J.U.
Kids will get sick a lot when they first start daycare. It is annoying and sad for parents to have to disrupt their schedules to take a child home and watch them feel miserable.
The good news is, they are building up their immunity and this too shall pass. The longer they are around other kids, the more their immune system will build. By the time they are 3 or 4, they will get sick even less.
My singleton went through this and by the time he was 4 rarely got sick. Now he's in first grade and last year I think he missed one day because of being sick. This year none so far. And he is bringing home the sickness to my twins so they are building up their immune systems too.
Just remember this too shall pass. I wouldn't rush to take them out of daycare, but that's my opinion.