Aidan and Callum are three-year-old twins.

Callum is about a year behind his brother in development, in everything from speech to growth.

Callum has a genetic condition called Prader-Willi Syndrome.

One of the most unusual characteristic of the syndrome is an insatiable appetite, which is ironic because these kids often start of as weak babies unwilling to eat, but once they develop an appetite they can't get enough food to feel full.

In addition, the syndrome results in a slow metabolism so children with Prader-Willi  Syndrome don't need as many calories as other kids the same age.

Dr. Andrea Haqq from the University of Alberta is currently studying the hormones that regulate appetite.  That research could result in a treatment.

Calgary's first fundraising walk for Prader-Willi Syndrome will be held this Sunday, August 15, 2010 at Edworthy Park. Registration begins at 10:30am.

For more information on the syndrome or to learn about the walk click here.

For more information on Dr. Haqq's research and how to get involved in the research you can call 1-780-407-7241 or email