Yes, diapers do come in size 8! Different diaper brands offer different sizes, so you may need to look at different options, but you should definitely be able to find diapers to fit your baby. Some of the brands that offer size 8 diapers are Huggies, Pampers, and Luvs. When you look at different sizes, be sure to consider the weight, waist size, and rise (height of the diaper). If the diapers you're looking at come in size 7, 8, and 9, a size 8 will fit babies that are approximately 28-35 lbs, have a waist size between 12 1/4 - 15 inches, and a rise of about 20 7/8 inches.
It's important to find the right size to provide the best fit for your baby and to prevent leaks and messy accidents. If your baby is in between sizes, it's generally best to size up and adjust the fit with the diaper's adjustable fasteners. Good luck finding the best fit for your little one!