My step-daughter was diagnosed almost 4 years ago, when she was 6. Her older sister and half-brother were tested when the youngest was diagnosed and they were negative. Through a coincidence, I met a distant cousin of my husband's and she and her five siblings all have Celiac. They have an American Indian background and I have since learned that this group has a higher incidence of Celiac.
1 interesting thing is that my husband's distant cousin grew up on a farm and never ate processed foods until after she married and it is when she married and started eating processed foods, that she began to have problems, went to the doctor, and was diagnosed. Because of her persistence, all her siblings were diagnosed too.
My husband and I plan on having at least 2 children together and we plan to have them tested for Celiac if they show any of the symptoms.
I really am enjoying reading all of these posts; I have learned so much!