The 60-year-old music mogul is a doting dad to five-year-old Eric - who he has with his girlfriend Lauren Silverman - but his long-time pal and former girlfriend can't see the 'X Factor: The Band' judge having any more kids because he's so ''fulfilled and satisfied'' with his little boy.
Speaking to Closer magazine, she said: ''I honestly don't know if Simon will have more children. I think he's so in love with Eric, and he's so fulfilled and satisfied, that there just isn't any love left.
''He's completely besotted with Eric. Simon was always a softie - I've always said that to people.''
The 'So Macho' singer dated Simon on-and-off for 20 years but she's admitted the jealousy she used to experience when she saw him with other women is no longer an issue.
She said: ''I used to suffer with jealousy sometimes, which is why Simon and I would always break up. But once you transition into the friend zone, there's nothing to argue about or get upset about anymore.''
The 56-year-old singer - who has adopted children Mgdalena, 14, and Zac, 13, with ex-husband Andy Willner - doesn't believe her former flame has changed over the years.
She said: ''Simon is a really, really loyal friend. I mean, we've been friends for decades and he's still exactly the same person - the same sense of humour and everything. He didn't change with fame.''
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