Here is the transcript of Two in One.
One day at Canterlot, Yuna was researching on her Journals 1, 2, 3 and 4.
Princess Yuna: Okay, Let's see what spell we can use.
Just then, She discovered the splitting and fusing magic skills and starts practicing.
Princess Yuna: Wow! Splitting and Fusing Magic. Awesome.
Just as Yuna was about to practice her magic, The door opened popped opened.
Dog: Hiya, Yuna!
Princess Yuna: Yaaah!
With Yuna spooked, She accidentally separated Cat, Dog, Devon and Cornwall.
Princess Yuna: Uh-oh! What have I done?!
Princess Luna: Yuna, Is everything alright? (opens the door and was shocked)
Princess Yuna: Oh no. (gulps) Trouble. Big trouble.
At the throne room, Princess Celestia and Princess Luna looked half disappointed.
Princess Celestia: Yuna, What do you think you were doing? You have to be more careful.
Princess Yuna: I... I didn't mean to...
Princess Luna: Your father, Your aunt and I were very disappointed at you, Yuna.
Princess Solarna: Look who's finally in trouble now, Baby Sister.
Hiro: That's enough, Solarna. (to Yuna) Look, Yuna. We don't want to stay mad at you, But you have to be more careful using the splitting and fusion spell before studying it.
Princess Yuna: I know, Papa. It was just an acciddent, I'll find a way to fix this somehow.
Princess Celestia: Take your time, Yuna. We know you will.
Soon, Yuna arrives at the Golden Oak Library for more studies.
Gyro Gearloose: Everything okay today, Yuna?
Princess Yuna: Yeah, But I accidentally split the CatDog, Devon and Cornwall in half with my spell.
Gyro Gearloose: Well, I sure hope you work on that spell of yours to fuse them back at will.
Princess Yuna: Gyro, I really appreciate your confidence in me. Do you always fix your mistakes whenever you did something wrong by accident?
Gyro Gearloose: Yes. And sometimes, I have to find my own way to fix my own problems with my invention.
Princess Yuna: Thanks anyway, Gyro.
Just as Yuna kept studying the spell, Winslow T. Oddfellow came to see her.
Winslow T. Oddfellow: Hiya, Yuna. How's your research coming?
Princess Yuna: Doing okay, Winslow. I was just researching how to fuse CatDog, Devon and Cornwall at will.
Winslow T. Oddfellow: Well, Good luck with that. You're gonna need it.
And Winslow took off while she makes sure she gets the fusing spell right.
Later that day, Yuna found the right spell in Journal 3.
Princess Yuna: Aha! (reading on Journal 3) That's the spell I was looking for.
Suddenly, She begins to hear a fight.
Cat: This is all your fault, Dog!
Dog: My fault, How is it my fault?!
Cat: If you hadn't startled Yuna, (punches Dog) We wouldn't be in this mess!
Princess Yuna: Settle down. It was an accident, Cat.
Dog: Yeah, Cat. Don't be mad at me, I'm sure Yuna will find a way to fuse us together again.
Cat: (sighed calmly) I really hope that your right about this.
Devon: How long do anyone think this'll take?
Cornwall: Who cares about that, I just hope you know the formula of your spell, Yuna.
Princess Yuna: I know the spell.
With quick thinking, Yuna was able to fuse CatDog, Devon and Cornwall back together again.
Princess Yuna: Problem solved.
Just as Dog splits from Cat again, He felt happier.
Dog: High Ho Diggity!
Devon: Well done, Yuna. I must say you have great magic in you.
Cornwall: Yeah, Way to go, Kid.
Princes Yuna: (beamed) I did it. I did it! I did it! I did it!
That night, Yuna was writing her journal about her day.
Princess Yuna: (writing Journal 4) Dear Journal, I've learned very well to split and fuse with my spell. It was so hard, I'd see anything else coming. But when in doubt, Split and Fuse anyone or anypony at will if you have to. Your owner, Princess Yuna.
So, Yuna puts her journal away and look at the stars.
In the ending credit, Yuna was just finished painting the Fabulous Shooting Star.
Princess Luna: Yuna, Everything alright in here?
Princess Yuna: Doing great, Mama. (looks at the picture of Doc Hudson) This is for you, Doc. This is for you.
With that said, Doc's picture looked at the audience and winked at them.