Kids don't consistently get sick during business hours. This is a serious issue in pediatric care. It's kind of an open secret, though, since everybody knows it but nobody does anything about it. Sick children are usually seen the same day.
Well-child visits are scheduled during the business day when my assistant is available. But sick visits can be done when necessary. Though not by regular office hours, I see children in the evening, early morning, Saturdays, Sundays, and holidays.
The office is closed on Wednesdays, but if needed, I see children in the morning or evening on Wednesday.