Benjamin Button: Some people were born to sit by a river. Some get struck by lightning. Some have an ear for music. Some are artists. Some swim. Some know buttons. Some know Shakespeare. Some are mothers. And some people dance.
Benjamin leaves his family at some point after his daughter's first birthday (1970), and definitely before her second birthday. But a 1973-1977 El Camino is parked in front of their house as he rides away on his motorcycle.