Wicked Costumes Kids Power Ninja Fancy Dress Costume

What size would you recommend for an average 6 year old. Measurements given only relate to small,medium,large etc. Thanks in advance.

I am trying to make the purchase but I do not understand why the price changes from 13.98 to 17.20 ... I have amazon prime and the packaging and shipp

what size would fit a 3 year old

Is sword included?