2 year old getting sick at school

K

Since the start of November, my son has gotten sick on and off with different things for almost the entire month. It seems to happen every time he goes back to his preschool class which he attends two days a week for only about 2 hours. I understand this can happen commonly as the kids are being exposed to viruses they’ve never been exposed to and it ultimately helps their immune systems become stronger. However I was just wondering if there’s anything that you can do to help this. Also if anyone gives their LO any type of multivitamin or extra vitamins that they feel make a difference when it comes to this. I know they say kids don’t need a multivitamin and should be getting everything they need from their diet , but since he’s been getting sick and not having his usual appetite, he is not getting all the vitamins he needs.