On 6 April 1920, Schrödinger married Annemarie (Anny) Bertel. Schrödinger suffered from tuberculosis and several times in the 1920s stayed at a sanatorium in Arosa. It was there that he formulated his wave equation. As has been noted above, Schrödinger had an unconventional personal life. When he migrated to Ireland in 1938, he obtained visas for himself, his wife and also another woman, Mrs. Hilde March. March was the wife of an Austrian colleague and Schrödinger had fathered a daughter with her in 1934. Schrödinger wrote personally to the Taoiseach, Éamon de Valera, to obtain the visa for Mrs. March. In October 1939 the "ménage à trois" duly took up residence in Dublin. Schrödinger fathered two further daughters by two different women during his time in Ireland.