Katie Price believes her eldest son is her "guardian angel".
Harvey and Katie Price
The 42-year-old former glamour model regards 18-year-old Harvey - who was born partially blind and also suffers from autism, ADHD and the genetic condition Prader-Willi syndrome - as her "best friend" and thinks there is a particular "reason" why she is his mother.
She told the new issue of OK! magazine: "He will always be my man cub and just wants cuddles from me on the sofa.
"I do think Harvey was sent to me for a reason. I've always had a caring side and wanted to look after someone. Sometimes I think it was meant to be...
"Through everything, Harvey has been with me. TV appearances too! He's my supporter, my son and my best friend.
"I believe he's my guardian angel and nothing will ever come between us."
Despite Harvey's disabilities, Katie - who also has Junior, 14, and Princess, 12, with first husband Peter Andre and Jett, six, and Bunny, five, with third spouse Kieran Hayler - insists she's never treated him differently to her other kids.
She said: "Just because Harvey has complex needs, I don't treat him any differently. I still make him empty the dishwasher and make his bed."
The teenager celebrated his milestone birthday in May and Katie couldn't be prouder of him - but she's amazed he's so grown up.
She said: "I'm so proud of the man he's become. He has such good banter and is so funny. He's definitely an entertainer. He takes after me...
"I woke up on his birthday thinking, 'Oh my God, where have the last 18 years gone?' It literally feels like only a year or two ago that I took him to his first day at school. It's crazy how much has happened in that time. In some ways I wish my kids could all stay little."
Harvey's dad, Dwight Yorke, has never played a role in raising his son and the 'My Crazy Life' star finds it "reassuring" that her oldest child is always with her.
She said: "He's the only child that no one can ever try to take away from me. The others have their dads, but it's reassuring for me that he's always by my side."
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