Why does a two month old baby have a ulcer mouth?

A. Mouth ulcers in a 2-month-old baby can occur due to several reasons, even though they are uncommon at this age. One possible cause is thrush, a fungal infection caused by Candida albicans, which can lead to white patches or ulcers in the mouth. Another reason could be irritation from feeding, such as a nipple shield or bottle nipple causing friction. Viral infections, like hand-foot-and-mouth disease, could also cause mouth sores, although these are rare in very young babies. Additionally, nutritional deficiencies (though unlikely in exclusively breastfed or formula-fed infants) or a reaction to certain medications might contribute. If the ulcers persist, cause pain, or affect feeding, consult a pediatrician to ensure appropriate treatment and care.