In general, It's most likely a common cold with very mild symptoms. Children start to get colds after about 6 months of age. Babies, toddlers, and preschoolers get about 7 or 8 colds a year. This decreases during the school-age years to 5 or 6 colds a year. Teens finally reach an adult level of about 4 colds a year.
The main reason your child is getting all these infections is that he or she is being exposed to new viruses. There are at least 200 different cold viruses. Your child's body will build up immunity against these viruses when he or she is exposed to them. But this takes many years. Your child will be exposed more if he or she attends day care or a preschool. Older brothers and sisters may bring home a virus from school. Colds are more common in large families. The rate of colds triples in the winter when people spend more time crowded together indoors breathing recirculated air. Smoking in the home increases your child's susceptibility to colds, coughs, ear infections, sinus infections, croup, wheezing, and asthma.
If your child is vigorous and gaining weight, you don't have to worry about his or her health. Your child is no sicker than the average child of her age. Children get over colds by themselves.