There are two possibilities that come to mind reading your description -
1. Blocked duct connecting the eye to the nose (NLDO) - in this case if you gentelly press on the swelling sticky whitish yellow discharge should come from the eye
2. Capillary hemangioma
- this is a abnormal growth of blood vessels. they may enlarge slightly when the baby cries or coughs. if its the latter then there are some medical therapies that do help resolve the same.
Pls consult your eye doctor as well as pediatrician
( in case of hemangioma) for the same.
Hope your baby has a speedy recovery and a bright childhood