With the finale just around the corner, Tim's down to the last few competitors. His wife, Anna Heinrich did the course last year, putting in an inspiring effort after the DS crew initially thought she'd only last a few days.
Upon receiving the letter from home, Tim opened up more about his relationship and his physical health.
"My wife is scared shitless for me, she thinks I'm going to fall apart," he laughed.
"I know when she did it last year, I was like, I'm glad you're doing it because there's no way I could do it at that stage," he said. "Mentally I could do it, but physically I couldn't."
"My body is starting to let me down more in certain ways, and it can affect me as a person and my energy with my wife, with my kid, so my motivation to do the course is to prove to myself that I'm not done yet," he shared.
Tim read out the letter to the other SAS recruits, tearing up as he read Anna's words.
"Don't worry about what's next, you can't control it," he read.
"And if you don't beat me, you'll never live it down," he laughed. "If that's not enough motivation for you I don't know what is... love, Number 12."
The letter was complete with a drawing from his daughter Elle.
Tim and Anna's exciting family news
After meeting on The Bachelor 10 years ago, last month Tim and Anna shared they're expecting their second child together in 2024.
The couple announced the happy news in a sweet video showing their 2-year-old daughter Elle walking around with what appears to be a ball or balloon in her jumper. "My mummy's going to have a baby soon," she said.
Tim and Anna confirmed the exciting news in the caption, writing: “Turns out Elle was right. Bringing another little rascal into the world 2024.”
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