She was the 975th to audition
Lori Martin (April 18, 1947 – April 4, 2010).
Lori Martin (born Dawn Catherine Menzer) was an American actress. At the age of 12, she was the 975th young hopeful to be auditioned for the role of Velvet Brown in the NBC television version of National Velvet, a role which brought her to wide attention. After being included in the final three, she was interviewed ten more times before winning the part. When she won the role, her name was changed from Dawn Menzer to "Lori Martin". The show ran for fifty-eight episodes between 1960 and 1962.
Martin appears on The Donna Reed Show in “All Women Are Dangerous” (Season 5 Episode 32) where she wants an invitation to Jeff's party.