Bella and Ben are 19.5 months apart. Ben's always been a little bigger, and Isabella- more petite. Ever since they were old enough to sit side by side in the shopping cart, I have occasionally been asked if they were twins! And I got asked again today. I could see how you would maybe say that if you didn't try to communicate with them.
Ben and Bella (watching Nemo) all cuddled up! And matching. :)