Simon Cowell and Lauren Silverman will live together and raise their baby as a family.
The 36-year-old socialite - who recently settled her divorce with Andrew Silverman - is pregnant with the media mogul's child and it is said the couple want to give their unborn baby a "proper" upbringing.
An insider told the Sunday People newspaper: "This is something Simon didn't ever expect to happen. He would sometimes say he wanted children but didn't actually believe it would happen.
"Now it has, he wants to grab the opportunity with both hands and be a proper dad. That means living with Lauren and actually being a family.
"He wants to be a good dad, just like he regards his own father ... He wants to emulate what his parents did for him. He knows how important a stable home is for a child."
It is also reported the couple aren't ruling out "marriage", but the 'X Factor' star's main "priority" is to care for Lauren and their unborn baby.
The source added: "He will stop at nothing to make sure that this happens and that means him and Lauren living together in a proper relationship.
"And who knows, maybe marriage will be on the cards. His current priority is to look after Lauren and make sure that she has everything she needs. He is really looking after her."
Meanwhile it has been reported Simon, 53, will become a full-time father and let his career "take a back seat" once he turns 60.
A friend told the Sunder Mirror newspaper: "It's hard to imagine Simon as a house husband and his work is his life, but he said it will be time to take a back seat in a few years.
"He has achieved everything he can with his astonishing career. And while he won't walk away from it all in a hurry, he is looking forward to the day when he becomes a full-time dad."
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