Sometime prior to the formation of International Rescue, Mrs. Tracy died in a preventable accident. It was the loss of his wife in such circumstances that drove Jeff to create the rescue outfit, so that no one else would lose anyone the same way he did.
After the Hood had taken control of Tracy Island and used the Thunderbirds vehicles to rob the Bank of London, the Hood tried to set Alan against his father by claiming that Jeff had deliberately left her to die. However, the tactic didn't work and the Hood was later overpowered (quite literally) by Alan.
- The depiction of Jeff's wife in the film is the only "physical" (i.e. not comics or other static media) depiction out of all three major Thunderbirds incarnations - the classic series, the film, and the 2015 animation. However, the actress that portrayed her sole appearance (in a photograph located on Jeff's desk), is unknown.