Yvette Gessard-Picard was a Human woman who lived in La Barre, France during the 24th century. She was the wife of Maurice Picard, the mother of Robert and Jean-Luc Picard, and the paternal grandmother of René Picard. Yvette was deceased by 2364. Jean-Luc affectionately referred to her as "Maman".
Yvette used to sing "come out, come out wherever you are" to Jean-Luc when he was a young child. (Star Trek: Insurrection)
As a child, Captain Picard took piano lessons; he dreaded the recitals. As he felt that he was not very good at playing the piano, he hated playing in front of large audiences. In later life, he regretted giving them up, as they pleased his mother. (TNG: "The Perfect Mate")
Background information Edit
A picture of Yvette was included on a page of the Picard family album that did not make it on screen.
In the comic book The Gift she was given the first name Christine.