Unique design by Hello Handmade - All our items are carefully handmade and handprinted by us. Made in the USA. We use professional permanent inks that last a very long time. Solid colors are 100% soft cotton, Heather colors are 90% cotton/10% polyester Gerber onesie size chart: 0-3 Months: 6-12 Ibs. weight, 21-24 in. height 3-6 Months: 12-16 Ibs. weight, 24-26 in. height 6-9 Months: 16-20 Ibs. weight, 26-28 in. height 12 Months: 20-24 Ibs. weight, 28-30 in. height 18 Months: 24-28 Ibs. weight, 30-32 in. Rabbit Skins Baby One-piece Bodysuit measurements: Newborn: 14.5" Chest, 11.5" Body Length (Up to 9 lbs.) 6 Months: 17.5" Chest, 12.5" Body Length (10-16 lbs.) 12 (12-18) Months: 19.5" Chest, 13.5" Body Length (17-20 lbs.) 18 (18-24) Months: 21.5" Chest, 14.5" Body Length (21-24 lbs.) ** For the baby onesie or bodysuit, we use either Gerber or Rabbit Skins. Rabbit Skins Infant & Toddler Shirt measurements (Armpit to Armpit): 6 Months (10" Body Width, 12.5" Body Length) 12 Months (11" Body Width, 13.5" Body Length) 18 Months (12" Body Width, 14.5" Body Length) 2T (13" Body Width, 15.5" Body Length) 3T (14" Body Width, 16.5" Body Length) 4T (15" Body Width, 17.5" Body Length) 5/6T (16" Body Width, 18.5" Body Length) Next Level Apparel Youth Unisex Short-Sleeve T-Shirt measurements width = Armpit to armpit: Small (6-7): 15.5" Chest, 20.5" Length Medium (8): 17" Chest, 22" Length Large (10-12): 18.5" Chest, 23.5" Length XL (14-16): 20" Chest, 25" Length ** Next Level Apparel Youth Light Blue Shirt is lighter in color than Rabbit Skins Toddler Light Blue shirt. Please contact us if you have any questions specially regarding size and we'd be happy to help :)