At her 90th birthday party (!) on Friday, Olga Hirshhorn — the widow of Joseph Hirshhorn, the founding donor of the Hirshhorn Museum and Sculpture Garden — said that one statue in D.C. in particular inspired her. She recalled that in 1965 or ’66, just shortly after she had married Joe Hirshhorn, the two were living in Kalorama and considering moving his art collection to a permanent home in Washington. (Take a wild guess…