Hello girls! I have a suspicion that the child has an allergy to cats …

Hello girls! I have a suspicion that the child has an allergy to cats from parents. How does cat allergy manifest in children? The child has swelling of the mucous membranes of the eyes, conjunctivitis and runny nose with tears. The eyes also stick together, and today he scratched his eyes like this. But I don't know, we also got sick at home (we don't keep cats) and now the parents have a cat. Damn, I don't know what to think.