Weight-obsessed

We are still obsessing about Katrina's growth patterns. She has an appointment at Johns Hopkins later this month as a 'second opinion' with a gastroenterologist. They (hopefully) won't rerun the tests but will look at the results and see if there is anything the doctors at Georgetown missed. I'm thinking about it now because I was over a friend's house this morning; their youngest daughter is a few months younger than Katrina and wears a size 6 diaper. (Size 6 is for kids who weigh more than 35 lbs.) In contrast, Katrina wears a size 4 diaper and they are huge on her ... I go back and forth with the idea of putting her in a smaller size. I know it's all relative, but our friends are average-to-tall in height, and both are athletic and slender. I am average height and Ryan is tall, and we both gain weight easily. So how do we have the skinny kid whose pants fall down all the time?? Our newest niece weighs just about half what Katrina does ... and she is seven weeks old. I'm sure Baby Bethany will pass Katrina in weight in her first year.