X Factor boss Simon became a first-time father on Valentine's Day, when his New York socialite girlfriend Lauren Silverman gave birth to his son Eric.
And, while newborn babies can often be quite a handful for a first-time parent, it seems Simon's experience has been a breeze. Well, according to his ex Terri, anyway!
Terri told Us Weekly: "He's such a happy baby. He wakes up, has his food, and goes straight back to sleep. He's like the dream baby. He's amazing."
TV host Terri added that Baby Cowell is "the most well-behaved baby" she's ever met, joking that's particularly impressive considering Simon is his dad!
"He never cries," she added. "I literally heard him cry once… and [he] sleeps from like, seven in the evening to seven in the morning."
Simon gave his first TV interview about baby Eric to Terri earlier this year, telling her he made it to Lauren's bedside in New York in the nick of time as she went into labour while he was filming Britain's Got Talent in London.
"Phone rings at half five in the morning: 'I'm about to give birth.' We had to find a flight, which we did, and I got there with two hours to spare," he recalled.
Simon said he held his son within five minutes of his birth and there were tears, adding he bonded with him immediately despite fearing beforehand that he wouldn't. "I had actually said to Lauren beforehand, 'What if I like the dogs more than Eric? I've never had a baby before.' She said, 'You'll be absolutely fine' and within seconds of him being born I got it."
The tiny tot's godmother is another of Simon's ex-girlfriends, X Factor regular Sinitta.
Celebrities who have welcomed babies in 2014 in pictures:
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