Complex sentence: Peltz's work was notably featured in the Oval Office during John F. Kennedy's presidency; the piece was a carved tern given to the President by his wife Jacqueline Kennedy, who was known to have personally owned at least three of Peltz's pieces.
Split into simpler sentences: Peltz's work was notably featured in the Oval Office during John F. Kennedy's presidency. The piece was a carved tern given to the President by his wife Jacqueline Kennedy, who was known to have personally owned at least three of Peltz's pieces.