my siblings have school aged children who see DS often- one of them just gave him a cold. this is the second time this has happened (it wa a virus over the s ummer).

so my question is - how bad is this? my son is 9 months old. I am worried that he has been sick more than the average infant with these 2 illnesses and wodering if this will have a positive or negative effect on his immunity in the future

anyone have any ideas?