Does medusa have a sibling

Medusa's Gorgon sisters were Sthenno and Euryale, the children of Phorcys and Ceto (or Ceto and Gorgo). Their sisters would be the Graiai: Deino, Enyo, Persis or Pemphredo. Ekhidna and perhaps Skylla, their brother is Landon, the Hesperian dragon. Another sister was Thoosa.