If it is an ophthalmologist who has examined the eye and told that it is not something that you need to worry about then it is fine. But if the lesion has not been examined by an ophthalmologist so far then it is better to get it done. Some of the congenital ( since birth) lesions are dermoid cyst
, conjunctival cyst
. As the lesion is growing, it needs to be monitered well and may even need further investigation such as MRI
scan or even a B-scan. Do get in touch with a pediatric ophthalmologist preferrably at the earliest.