I ordered 12-18 months and my daughter wears a US size 3.5.
They're big enough to have room to grow with age, but not too big for her to wear now.
Slip-Resistant Crib Shoes for Babies: Robeez Soft Soles for Girls and Unisex Toddlers, Ages 0-24 Months
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DREAM PAIRS Little Aurora 03 Communion Shoes and Flats for Girls - Top Choice for Stunning Style and Comfort
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Felix Flora Toddler Flower Dress Shoes - Adorable and Comfy Flats
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Stylish and Comfortable pediped Flex Estella Mary Jane Shoes for Toddlers and Little Kids
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KUBUA Sneakers Lightweight Breathable Athletic Girls' Shoes for Athletic
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Saucony Girls Cohesion Running Little
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LEOCI Soccer Shoe Coomfortable Numeric_11_Point_5 Girls' Shoes and Athletic
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Breathable Fashion Sneakers for Baby & Toddler Boys & Girls: Bless Children Walking & Running Shoes
54 Review