- Sidetable Drawer
- Mr. Salt
- Mrs. Pepper
- Slippery Soap
- Marty McParty
We play Blue's Clues to figure out what Mailbox's birthday party is.
- Question: TBA
- Clues: TBA
- Answer: TBA
- Wrong Answer TBA
- Skidoo: Birthday World
- This episode has premiered on April 28, 2021 in the UK according to NickALive. It will be released on US TV, but on an unknown date have to wait for unknown date.
- This is the third episode to premiere on TV outside the US.
- This is the first reboot episode where the viewers get a letter.
- Birthday World is very similar to Birthdayland from Blue's Birthday Adventure.
- It is located in the Living Room Picture Frame, the same area as the Present Store from the original episode.
- This is the second time mailbox's birthday is celebrated.