Battling Upper Respiratory Infetions in 7 year old With DS

Adopted our sweet boy a few years ago. Has hirschprung's disease as well had a tracheostomy and g-tube since birth. Trach and g-tube were removed last summer (YAY!!)

School seems to be very tough on him in terms of catching EVERYTHING. We went the whole summer without as much as a runny nose, and now 2 weeks back at school and had to stay home today due to a nasty cold.

Does this get better? We use the saline in the nose but obviously with the immunocompromisation and only being a year trach free, we can expect this. I would love to hear from the community. Tips and tricks, remedies that worked and don't.

Thank you!!!