We report a mother and adult son with a unique variant of CED featuring a generalized skeletal disorder with the histopathological characteristics of osteomalacia and alterations in two genes that importantly regulate skeletal homeostasis: TGFβ1 and TNFSF11, encoding TGFβ1 and RANK ligand (RANKL), respectively. This evidence concerns the gene TNFSF11 and osteomalacia.