Sharing a throwback baby pic of Harvey, now 16, with his estranged dad, footballer Dwight Yorke, the former glamour model pleaded with her ex to get in touch, adding: "It's never too late - the door is always open."
In a lengthy caption, Katie, 40, wrote: "Harv as a baby, just found these pics. I am so proud of the person he has become."
I am so proud of the person he has become.
She also referenced Harvey's disability, which includes blindness, Autism and Prader-Willi syndrome, writing: "For any of my followers bringing a child up with complex needs I admire you ❤️ it's not easy but it is totally worth it."
And seemingly addressing the 47-year-old former Manchester United player - who has reportedly not seen his son since he was a baby - Katie wrote: "To who has never been there for him just remember it’s never too late. The door is always open..."
Next to a second cute baby snap, Katie later added: "So innocent ❤️ I will be donating and supporting tonight for #BBCCIN #childreninneed are you? ❤️❤️❤️❤️."
Her 1.9million followers rushed to offer support, with one writing: "💙✨A born star bless him he truly is a wonderful young man... all credit to you Katie for standing by him alone x."
Another added: "This is an amazing thing to say ❤️ x."
A third wrote: "Those last two sentences @officialkatieprice, very admirable. I wouldn’t want him near me if I was you x."
It comes as rumours fly that Katie is back with her ex-boyfriend, Kris Boyson following a late-night tweeted proposal.
She later denied headlines that she'd been wedding dress shopping though, writing on Twitter: "Completely wrong untrue story again, actually Adrian making me a Christmas outfit."
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