My son seemed to have a cold, so my wife took him to hospital.
Then the nurse told him, “Oh! You are playing quietly today.”
I wonder how noisy he is usually?
so my wife took her to the hospital.
→ took him かな？、hospital は the なくて ok
I wonder how much noise does he usually make?
→ 間違っていないけれど、how noisy he is usually? のほうが自然かな