My son keeps getting sick at daycare: Advice?

My almost-three-year-old son goes to daycare on a Monday, just one day a week, just for the socialization side of it. Every week he is catching a cold/snotty nose. Then I have to keep him home the next week until his colds are resolved. The following Monday, I send him, and he wakes up on the Tuesday or Wednesday snotty again! It’s a draining cycle. I’m wondering what I can do to boost his immunity? He is a fussy eater and doesn’t eat many vegetables. He does eat fruit. I’ve started him on an immunity booster powder that the pharmacist recommended. Is there anything else you Mumma’s swear by to avoid your child getting sick every week at daycare?? Help

Sounds like he hasn’t had enough exposure to other kids and their germs. He could also be allergic to something that is at daycare that you don’t have in your home. Essential oils are amazing at helping this kind of stuff.