Ellie is 3 months old and weighs 10lbs 15oz. She was 7lbs 8oz at birth. She never dipped below 8% weight loss from birth weight but enzymes were started at 2 weeks old. She is severely pancreatic insufficient. Her last weight was taken 2 weeks ago and she weighed 10lbs 7.5oz. The doctor/dietician would like to see greater weight gain due to the higher BMI and better lung function correlation. Her older brother has always been around the 25th percentile in weight and both myself and husband were slender children. I'm thinking we're combating the tendency to stay thin based upon our genes in addition to her having CF. My question is at what time did your child's doctor become concerned about slow weight gain? We're fortifying my breastmilk and feeding her a sufficient volume and then some. She only passes stool 1 to 2 times daily so it's not an issue of malabsorption. I guess I'm just curious if others have had this problem and what you were advised to do? At what time do you worry and when would a doctor suggest a g-tube? Thanks....