Ecco's conversion from EU to UK sizes
 
EU19 - UK 3.5 (Toddler)
EU 20 - UK 4
EU21 - UK 7
EU22 - UK 5.5
EU23 - UK 6 - 6.5
EU24 - UK 7
EU25 - UK7.5 - 8
EU26 - UK 8.5 - 9