Simon Cowell thinks fatherhood has transformed his life

Simon shared: "My life is very different since he came along. It was my 59th birthday last week and it started with me taking Eric out cycling, with him dressed as an alien. Then I bought him yoghurt, watched him play in his hamster wheel on the grass, we had a swim and I taught him how to ride a quad bike."

Despite the added responsibility of parenthood, Simon feels happier now that he has done for a long time.

Reflecting on how he spent his birthday, the 59-year-old star told the Mail on Sunday newspaper: "Lauren was in New York seeing her son Adam, so I ended up getting sloshed with a friend of mine at Nobu in Malibu.

"And when I woke up the next day with a hangover, I thought about what a great day I'd had and how I do feel happier than I have done for a very long time."

Simon also claimed that his decision to shun his mobile phone has helped to improve his overall mood.

He said: "There was one morning a year or so ago when I woke up to 25 unread text messages and I thought, 'I'm really not in the mood to read those today.'

"So I left it a week and it went up to 200 unread messages ... So I thought, I'm just going to turn the phone off for a month and I'll get back to it then. And I never turned the phone back on again after that day.

"Then I worked out that I was doing over 1,000 meetings a year, which with the phone too, was getting crazy. In my 20s we used to have an answering machine at home and there were never any messages, and I was happier then.

"Now, if you lose your phone, it's worse than losing your wallet. I lost one once and I thought, 'My God, I've lost my life', but it's just a stupid phone!'"