[citation needed] Stemberger studied cello at the conservatories in Vienna and Salzburg.

After graduating in 1988, she began her acting training with Eva Zilcher.

She and her sister Julia Stemberger are the daughters of the tropical medicine Heinrich Stemberger and the actress Christa Schwertsik, who is married to the composer Kurt Schwertsik.

Through her husband Fabian, Stemberger is the daughter-in-law of Bibiana Zeller (1928–2023) and Otto Anton Eder (1930–2004).

The couple Schwertsik and the Stemberger sisters make common theater, such.