Kottanner married twice and bore three children. Her first husband was Peter Székeles (or Gelusch), a notable patrician in Sopron. He was already a member of the local magistrate in 1402. He served as mayor of the town from 1408 until at least 1421. He died in 1430 or 1431. They had a son, William, who lived in Austria and was involved in a lawsuit over a meadow in Sopron in 1435. Because of his illness, he did not present before the court personally, but represented by his stepfather and maternal grandfather. William was still alive in 1437.