Kids’ Immunity Booster that actually works???

Can anyone please recommend a multivitamin/supplement for children that has actually worked for them. I know it’s normal for kids to get colds as their immune systems develop, but despite all the extra hygiene and social distancing, we have been hammered with viruses this winter. We eat fairly well - lots of garlic, fresh fruit and veggies etc - but am hoping that there may be vitamin that will help. I’ve been skeptical in the past, but willing to give it a go if it’ll make a difference. I’ve Googled the heck out of it and there’s sooo many, it’s overwhelming. Thank you!!