 The fifth and youngest son of Jeff Tracy (the founder and financier of International Rescue), Alan is named after American astronaut Alan Shepard.Sources differ on the subject of Alan's age and date of birth; in the "Thunderbird Fact File", his birthday is stated to be 12 March 2044, making him 21 years old during the events of most of the series (he turns 22 in the episode "Attack of the Alligators!