It's the Sumatra. The charts I've read said there is a possibility of a "tinted" egg. This egg is a very light brown/buff color and it is small. The Sumatra is a small hen so it all adds up. Mystery solved and she barely misses a day of egg-laying. We have 10 hens-3 bluish green eggs (EE), 1 big brown/pink egg (EE), 3 large white eggs (Leghorns and Spanish), 2 smallish white eggs (Hamburg and Polish), and 1 small tinted egg (Sumatra). It is quite fun being able to pick out who is laying and who is lazy ha ha!