Brief Answer:
Advise taking him to his doctor for confirmation of diagnosis first

Detailed Answer:
Hello and welcome.

Thank you for writing to us.

I have gone through your query with diligence and would like you to know that I am here to help. Well, the first thing is to find the cause for the swelling which only a doctor can do with the help of a physical examination and other investigations (e.g. ultrasound examination).

Let me first go ahead and list all the most common causes for such a presentation in a child his age:

+Orchitis: Inflammation of the testicle(s)
+Mumps: Viral infection with flu-like symptoms
+Epididymitis: Swelling of the epididymis which is a tube behind the testes
+Hydrocele: A fluid filled sac around the testicle
+Torsion of the testicle
and a few other causes.

I would thus recommend a visit to your son's doctor, for confirmation of his diagnosis and treating him accordingly. In the meantime, please feel free to write back to me for any further clarifications, I am always here to help.

Best wishes.

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