Hello Handmade design - All our items are carefully handmade and handprinted by us.  We use professional permanent inks.

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. 

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 Months: 19.5" Chest, 13.5" Body Length (17-20 lbs.)
18 Months: 21.5" Chest, 14.5" Body Length (21-24 lbs.)

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)

Youth 100% Cotton Short-Sleeve T-Shirt measurements (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

Please contact us if you have any questions and we'd be happy to help :)