3 children, 2 male and one female, affected by Ehlers-Danlos syndrome, types I or dangerous, III or mild familiar hypermobility, and (II or V)? or intermediate. The types I and (II or V)? normally affect the skin and the lower extremities, in the form of breakable skin, hyperelasticity... The type III predominantly attacks the joints and tends to dislocate bones. In the dermic distant zones, the skin is thin with excessive folds. The importance of early detection is due to prevention or control or the complications (depending on the type of illness), and inform about the genetic risk, based in a correct typification, this has clinics difficult because there are intermediary forms and it is necessary a specialized laboratory in collagen's studies.