I ordered shirts today! I was worried about the sizes too, but just guessed based on their size chart. I can get away with a Med, but ordered large just in case, and for my son, who is a 4T normally, I did an XS instead of an XXS. I know that doesn't really help much. I just figure better to be too big than too small. They have a great deal though with the $5 shirts, and then 15% off if you have the Disney visa and only $5 if you spend $50. I ordered 6 adult shirts, 4 kids shirts, and an infant onesie for $56 including shipping.