The former couple - who have six-month-old daughter Dream together - ended their turbulent on/off relationship three months ago, but that doesn't mean the 30-year-old reclusive sock designer doesn't still have feelings for his ex-fiancee.
Sharing a picture of the model when she was a teenager on the photo-sharing app on Tuesday (30.05.17), Rob wrote: ''On my first episode of Rob's Random Cornball Thoughts is This young lady who grew up to be the woman I love and the mother of my child. She is beautiful and gave me my first child @blacchyna (sic)''
The 'Keeping Up with the Kardashians' star shared another picture of the 29-year-old brunette beauty - whose real name is Angela White - in Spongebob Squarepants shorts when she was just 14 years old.
He captioned the photo: ''Awww look at my little Angela at 14!!!!!! Hahahaha I LOVE YOU !!!!! @blacchyna (sic)''
Though they have recently been seen looking more cosy on Snapchat, insiders insist the pair are not back together, but they have been hanging out as friends for the sake of their little girl.
A source previously said: ''They are co-parenting and independently working on themselves but they're more cordial now than they have been, which is why they hung out recently. But by no means are they back together.''
Chyna has also recently moved into a new home as she wanted a bigger space and is now closer to her Lashed Salon.
The insider added: ''She's really excited about this house and she's been busy nesting.''
Rob still gets to see his daughter on a weekly basis and is ''always so happy'' to spend time with her, especially as her personality is changing and developing every day.
The source said: ''She's not quite rolling over yet but she is very giggly, laughing at everything and has a million new facial expressions.
''She's starting to watch and absorb cartoons now. It's so cute.''
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