Has your little one had croup before?⁠ Casey here - my youngest child has had croup several times; my eldest has never had it! ⁠ ⁠ Croup is more common in winter and mainly affects children between six months and five years old, but it can affect older children. ⁠ ⁠ Croup is a condition caused by a viral infection. The virus causes swelling of the voice box (larynx) and windpipe (trachea), which narrows the airway and makes breathing harder. ⁠ ⁠ Croup can get worse quickly. If your child is havi