While he has spoken on TV earlier this week, Rob's appearance on Good Morning America marks the first time he has talked in an unrecorded interview.
So basically, if he messed it up — it would be in front of hundreds and millions of people — no biggie, eh?
We reckon he was nervous, especially after seeing some of the faces he was pulling on the way into the studio!
Rob seemed even more nervous in the studio, constantly cracking jokes and trying to move the conversation along.
However, the host was keen to address 'the elephant in the room'.
He asked Rob: "Everybody just wants to know... how are you doing? What do you want your fans to know about what's going on in your personal life?"
Rob looked uncomfortable and answered dodged the question.
He said: "My fans seem pretty excited about ... kind of whatever":
To which they proved this, and cheered wildly from outside.
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The host pressed things further, but Rob was not prepared to talk about what had happened and instead, tried to divert everyone's attention with a box of cereal.
Well, it was morning after all.
So what would you like your fans to know, Rob?
R-Pattz grabbed the box and said: "I'd like my fans to know that Cinnamon Toast Crunch is just 130 calories."
He then gave in, slightly, and said: "'Pretty much everything that comes out of my mouth is irrelevant."
Before adding: "You go into it to do movies. I'm never been interested in trying to sell my personal life. The reason why you go onto TV is to promote movies."
Yeah, we are starting to think he might not want to talk about all this.