Conversation so far:
When was the Whitney Museum of American Art created?
The Whitney Museum was founded in 1930.
Who was Whitney Museum named after?
Named after the museum's founder, Gertrude Vanderbilt Whitney.
Who was Whitney Gertrude?
Gertrude Vanderbilt Whitney was a well-regarded sculptor as well as a serious art collector.
How did the Whitney Museum of American Art begin?
In 1929, Whitney offered to donate over 500 works of American art to the Metropolitan Museum of Art, but the museum declined the gift.

Question: What did she do when she was declined?
Self-contained rewrite: What did Gertrude Vanderbilt Whitney do when she was declined by Metropolitan Museum of Art when offering to donate over 500 works of Ameircan Art?