Rob told his five million followers that he was looking forward to spending America's Independance Day (today) with his little boy, watching fireworks with him.
The Keeping Up With The Kardashians star said: "Happy I got my son with me for the 4th!! Can't wait to watch fireworks with my little man! Hope everyone is safe!"
Unsurprisingly, Rob's tweet left us and the rest of the Twittersphere saying: "Eh?! ROB HAS A SON?!"
A few hours later, however, the sock designer posted a new message on the social media site, revealing to his fans that he was in fact jesting with us.
"Those who know me know I play and I do NOT have a son," Rob tweeted. "Y'all got my mama emailing me asking if I have a son. Lol goodness hahaha."
You old joker, Rob. We can just imagine Kris' reaction when she heard your 'news'...
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