Have just been on the Boden site, looking at clothes for my dd and reading the reviews of various items. Soooo many of the reviews complain about the clothes being too small and people having to size up for them to even fit their children. One of the reviewers complains that she had to buy size 12 to fit her 'normal' 6 year old in the cropped cargos for girls.
AIBU to think that these kids are not normal, they are huge!
I have boden age 4-5 for my slightly petite 5.5 year old and the sizes are generous. Even if she was average for her age she would still only need 5-6.