Personalized Blue Octopus Grandpa's Sweetheart T-Shirt. This is the Blue Octopus Grandpa's Sweetheart design. It's a great gift for grandchildren or anyone who is the grandma's sweetheart in their family! The design is based on a traditional octopus kite, but with a cute, kawaii twist that makes it perfect for grandparents or grandchildren Wardrobe essential for looking good, 24/7. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar. Shoulder-to-shoulder taping. Double-needle stitched sleeves, bottom hem and front neck. Note: greys are a cotton/polyester blend.