person A: My son got his first ear infection last week.
person B: Uh oh. Is he better now?
person A: Yes_comma_ thank goodness.  The antibiotics fixed him right up.
person B: OK_comma_ good. What do you think caused the infection in the first place?
person A: The doctor mentioned his congestion might have contributed_comma_ but I got the impression that they just happen sometimes with no real cause.
person B: Is he a baby? I heard it happens often.