Personalized Twin B (i'm younger) Baby T-Shirt. Twin B (i'm younger) Baby T-Shirt - White. Colorful baby tee that’s ready for a name or your own funny baby quote or insider family joke. The only thing ‘cuter’ than babies themselves. 100% ring-spun cotton. Ribbed crew neck. Taped shoulder-to-shoulder. Double-needle hem sleeves and bottom. White is sewn with 100% cotton thread.