Today is Donny Dolphin's birthday, but since he was born on a Leap Year, he only gets to celebrate his birthday once every 4 years. So Baby Lamb and Cow help Donny have the best birthday ever by helping him do the things he wants to do. Only things get a little out of hand in the process.
Baby Lamb and Cow wonder why the house looks slightly different and they figured someone did some remodeling. Donny excitedly meets up with the two and want them to ask what today is. After several unsuccessful hints, Donny reveals to Baby Lamb and Cow that today is his birthday. Baby Lamb wonders what today is, and Donny says that today is February 29. He explains to them that it happens once every four years, signifying that the year is a leap year. Because his birthday's on Leap Day, he doesn't get to celebrate his birthday as often as everyone else. Cow asks how old Donny is turning, so Donny says he's 10 years old in leap years because he doesn't think counting all the other regular years do not count. Donny wants to make his birthday extra special otherwise he would have to wait 4 more years to make up for it. He laments over how other people get birthdays that they celebrate every year but he doesn't have that advantage, so he enlists Baby Lamb and Cow's help in making his birthday special. They both gladly oblige and Baby Lamb asks Donny what HE wants to do.
Donny brings out a long list of stuff he wants to do, and the first thing he wants to do is see how long he can be inside a dragon's mouth. The Dragon shows up, and Donny gets inside his mouth and asks to be carried. The next item on his list is having a jousting tournament with Thomas the Tank Engine, with Calfy riding inside. They both charge at each other, but stop before they were about to hit each other. Though confused, Baby Lamb and Cow wonder what's next. Donny says that he wanted to fly a helicopter, but he has since developed a fear of helicopters. So he moves on to the next item: prank-calling the President. Only, it turns out The President pranks Donny instead. Next, Donny wants to pants Mickey Mouse, which he successfully does (leaving Mickey naked) and then kicks him. The final item on the list is for Baby Lamb and Cow to push him off the edge of a cliff, thinking that he would survive since he's a Leap Year Baby. Baby Lamb and Cow think he's crazy and is getting carried away because he's born on a rare day. They don't want him to risk hurting himself on his birthday/
- Donny Dolphin
- Baby Lamb
- Cow McMoo
- Calf McMoo
- The Dragon
- Ricky Bowers
- Bill Quackers
- Mejax Webster
- Belle Butterfly (cameo)
- Alice Pennington (cameo)
- Uncle Lamb (cameo)
- Mickey Mouse
- This is the first (and probably only) episode to be uploaded on a Leap Year Day.
- This is also the first and only Baby Lamb Creations video to be uploaded on February 29.
- It's revealed that Donny was born on February 29, 1984. This makes him 36 (or 10 in Leap Years).
- Apparently Donny has to lie about his age when he got a job as a psychiatrist.
- This is the first full episode since Season 1 not to begin with the usual Baby Lamb Creations logo.
- Instead, the opening titles for the episode parody the Paramount Noveltoon cartoon opening titles.
- Instrumental arrangements of "Holiday Road" by Lindsey Buckingham, "All in a Day" from Caillou, and "Just Imagine" from Barney and Friends play in this episode.
- Cow thinks that "Leap Year" refers to Zoboomafoo.
- Donny said that he wants to fly a helicopter but after "what happened last month", he developed a fear of flying in a helicopter. This is a subtle reference to the tragic helicopter crash of January 26, 2020 that killed Kobe Bryant, Gianna Bryant, John Altobelli, Keri Altobelli, Alyssa Altobelli, Christina Mauser, Sarah Chester, Payton Chester, and Ara Zobayan.
- When Donny kicked Mickey Mouse after pantsing him, he said "Bob Iger can't help you now, Mick.", referencing how Iger stepped down as CEO of Disney at the time of this episode's production and was succeeded by Bob Chapek. Although Iger has since returned to the position as CEO as a result of the coronavirus pandemic's economic impact.
- The Happy Days theme song is playing in the background while Donny is prank-calling The President.