Justin Bieber adores his mom, Pattie Mallette, but that doesn't mean she's immune from outbursts from the star when he thinks he's being treated unfairly. Case in point: When her book deal for 'Nowhere But Up: The Story Of Justin Bieber’s Mom' was being worked out, Biebs was really mad when Mallette assumed he'd appear on the cover.

“When Justin’s mom initially signed her book deal it included an agreement that Justin would appear on the cover with her, but she signed this deal without his consent,” a source told Radar Online. “When things with her book finally started coming to fruition, she approached him about being on the cover and he threw a massive hissy fit. Justin felt like it was unfair to him.” And apparently this all went down before a show!

Here's the thing: He's right. She shouldn't have agreed to use his image without asking first, but she's also, you know, his mom. So we can see both sides of this.

The source revealed that Bieber's argument with Mallette got so heated that his everpresent manager Scooter Braun had to jump in and smooth everything over.

“It was literally a screaming match in his dressing room and Scooter had to step in and tell them that it was not the appropriate time or place,” the insider said.

Bieber wound up compromising: He didn't appear on the cover, but he did help to sell a few copies by appearing in person with Mallette at press conferences. “He finally broke down closer to the release of the book and agreed to do a press junket with her for the big outlets to promote it, but the whole thing was so awkward and uncomfortable,” the source said.

Don't get Biebs wrong: he adores his mom, but he feels like people constantly want something from him. “Justin knows that Pattie has a completely unrealistic existence thanks to him. She was a part of the process, absolutely,” the source admitted. “But the little s--- does work his a-- off.”

Harsh words, no? Just a word of advice to our beloved Biebs: If you're worried about people taking advantage of you, take a gander at the creeps who use your cars before looking at the lady who gave you life!

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