Hello, may daughter is 13 yo soon. She has been always very skinny, heigh is in the average, but since ever she is underweight. I (41 male) was like her and started to pick up weight around 10 years ago. No Marfan cases in the family, however my daughter has severe scoliosis and will have surgery soon. I read some time ago that hypermobile people has more chances to develop scoliosis and then I was addressed to a page about Marfan syndrome (also to other syndromes). She is indeed a bit hypermobile especially in the armpits, but no Marfan signs on the hands. She has no other signs to be affected by this syndrome, however, maybe because I am getting a bit hypochondriac after her scoliosis problem, I am wondering if I need to take up the subject next time we have a doctor appointment so we will have an aorta check and sleep quiet. But in the end I feel like that I am worrying about Marfan just because she is skinny.