| Please note the following:
"Bowser Junior's 9th Birthday!" is the 330th episode of SML Movies.
Bowser Junior is grounded on his birthday! But that won't stop him from throwing a party!
Bowser is finally ready to watch Charleyyy and Friends, but Junior comes in and announces that it is his birthday. Bowser forgot about Junior's birthday, so he tells Junior that he should wait until next year. Junior gets upset that he can't have a birthday. Then Charleyyy and Friends comes on the TV. Junior complains about the fact that he cares more about the show than him and smashes the TV with a hammer. Infuriated and devastated Bowser slams him into the broken TV. He then drags Junior to his room and throws him there, saying that he is grounded. Bowser Junior at first thinks that he can't get grounded on his birthday but Bowser says bad kids don't have birthdays. Junior at first says it doesn't matter because he forgot about his birthday, and Bowser tells him that Chef Pee Pee was throwing him a surprise birthday party downstairs. But he ruined it for being impatient.
Bowser drags Junior to the kitchen where there's a party set up. Chef Pee Pee yells "Happy Birthday Junior!" and balloons are released afterward. Bowser then drags Junior away and tells Chef Pee Pee to throw it all away. Chef Pee Pee complains and tells Bowser that it took a long time to get the party ready, but complies. Bowser drags Junior back to his room and throws him there. Junior tries to apologize to his father about the whole incident but Bowser yells at him saying that his apology will not work at a time like this and Junior furthermore proved to his father that he doesn't deserve a party and that he just can't be patient before a surprise birthday party.
However, Bowser changes his mind and reenters the room, telling Junior that he can have the party. Junior asks if he's serious, but it turns out that it was just Chef Pee Pee in a costume who says "Nah it's just me n***a!" and runs off laughing. Junior yells that it's his worst birthday ever.
Bowser answers the door to find Joseph and Cody, who showed up for Junior's party. Bowser tells them that the party is cancelled and slams the door closed.
The scene cuts to Junior's bedroom where Junior was sitting on his bed in despair until he sees Joseph and Cody knocking on the window. He lets them in, and Joseph and Cody give him presents. Joseph gives him an emoji poop cookie, and Cody gives him a board game: Soggy Doggy. Junior still wants to have a party though. Then they come up with a plan to trick Bowser and Cody and Joseph disguise themselves as Archibald P. Chapman and tell him Charleyyy is at the gas station which makes him rush there. Then Junior tricks Chef Pee Pee to set up the party again, dressed as Bowser.
Then Junior invites all his friends over, and Cody is drunk on root beer and tries to hump Junior, and then he makes Toad, blindfolded, pin a star on his dad to defeat him because he didn't let the party happen and Toad gets a bullseye. Then Cody fires a morphing gun at a Dinosaur balloon to make it come to life and the dinosaur destroys the party table. Then Brooklyn T. Guy shows up as a Police Officer and says he is here to make a disturbance complain, but it's because they weren't making enough noise and then he joins in. But then Bowser comes home and proceeds to go check on Junior when he realized that he was out of his room.
Bowser begins to snap when he sees Junior out of his bedroom and was about to punish him harder until he realized that the party sounded like fun. Then they go to the Birthday Cake and Junior makes a wish, which is to overuse a joke and blows out the candle, and Chef Pee Pee pops out of the cake as part of the “Nah, it’s just me n***a” gag, and the video ends.
- Bowser Junior
- Chef Pee Pee
- Brooklyn T. Guy
- Pablo (joke only)
- Chilly (joke only)
- Chef Poo Poo (puppet only)
- Donald Rodriguez (cameo)
- Charleyyy (In TV)
- Sonic (cameo)
- Toadette (cameo)
- Mario (Party banner)
- Luigi (Party banner)
- Donkey Kong (Party banner)
- Yoshi (Party banner)
- Peach (Party banner)
- Bob-omb (Party banner)
- The Bowser puppet from "The Perfect Plan!" is used again, but as a disguise only.
- This video marks the return of the T-Rex from "The Past Machine!"
- This is Toad's first speaking appearance since "Picture Day!"
- The Chef Poo Poo puppet is used again at the end of the video.
- This is the second shortest birthday special, with the first being "Chef Pee Pee's Birthday".
- This is also the first time Cody is seen without glasses in the thumbnail.
- This is Toadette's second appearance in 2017 and the first being "Substitute Teacher!"
- The birthday cake in the thumbnail is reused from "Jeffy's Birthday Wish!".
- This is the 6th time the Charleyyy and Friends theme song/full intro is played.
- When Junior broke the TV, it is similar to how The Cat In The Hat broke the TV in "The Cat In The Hat".
- This is the 3rd video in a row to have Patrick.
- The gun used to turn the dinosaur balloon into the T-Rex is the same gun used to shrink stuff shown in "Picture Day!"
- If the viewer looks closely at Patrick he looks different in this video.
- This is the final video of September 2017.
- When Junior gets his Soggy Doggy Board Game Present Cody says they haven't done a game night all year (hint) meaning that they might do a Game night video soon and Junior says they'll do a game night when their week is lazy.
- The Sonic the Hedgehog from Tito's channel, Titototter, is seen as a cameo between Patrick and Felipe when the party starts at 6:46. After that, he's not seen for the rest of the video Along with Toadette
- This is the second time Cody gets drunk, the first time being in Root Beer!.
- In the behind the scenes, Lovell said, "Nah it's me n*gga! Got your a** again! But happy birthday though!!" He said it in a higher, and louder voice, but Logan relaid the audio from Bowser Junior's Doll!.
- As of August 22nd, 2019, this video has been deleted, possibly because of Toad saying "Where the Hoes at?" after putting down the boombox, or Brooklyn T. Guy Chef Pee Pee naked and child abuse.
- When Cody makes the dinosaur balloon come to life, Tito can be seen in the costume when the T-Rex is roaring.
- Pablo and Chilly can be clearly seen holding Toad, Brooklyn T. Guy, Chef Pee Pee and Joseph at 9:36.
- However, when Logan found out about this, he embraced it as a joke to enhance the video. Because it looks like they're at the party too.
- At 5:04 Junior makes a grammatical error when he says “I can’t believe you actually guys did it!” When it should be, “I can’t believe you guys actually did it!”
- When the T-Rex destroys the party, Felipe can be seen lying on the table when he fled with everyone the scene prior.
- At the end when Chef Poo Poo says, "Nah, it's just me, n*gga!", the audio from Bowser Junior's Doll! where Chef Pee Pee closes the door can be heard as soon as he leaves, clearly meaning that the audio from said video is reused.
- When Cody and Joseph were on Junior's roof, Jeffy's crib can be seen in the reflection from the window.
- When Bowser grounded his son for his actions, he did not take away his toys like in Bowser Junior's Doll!. This could be due to the video being non-canon or Bowser might have tried to be a bit easy on Junior when he punished him.
- For some reason before and after the dinosaur comes to life, behind the dinosaur, there is a random toy wheel on the ground behind one of the curtains.