Texas Tees Sister and Brother Sibling Shirts, Hipster Design, I'm The Big Sister Brother Amazon size chart is not specific to our brand. You should not use it to pick the size you need. Please see product description below for more information on the sizes of our shirts Cotton T-shirts for comfort and softness. Both T-shirts are included in price. Cute screen printed design with Crew Neck for T-shirt. We have many other designs to choose from. Click on our brand name above the title to see more.