In common, blocked tear duct is a result of an improperly formed tear duct that obstructs the tear drainage system. And referring to some researches, when the duct cannot drain the tears, they have nowhere to go and may collect in the eye and cause irritation. In that way, it will just have some dangerous symptoms. And it will be more serious for children too. At this moment, you can just try milk, which is often recommended by pediatricians as a treatment for children with blocked tear ducts. Anyway, you can have a try.