It was a bright day. Everyone was (still) residing in the little mushroom house, and it was on that particularly bright day that a letter came for Mario.

"Mario, you got a letter from Rosalina," Peach yelled through the tiny house.

"I did?" Mario asked from his bed. He took it from Peach. He read it. "AAAAAH!" he screamed.

"What? What happened?" Luigi asked, startled awake from his nap.

"Rosalina's coming over just because she wants to!" Mario yelled. "You know, just to spend time with us." He added.

"Who's that?" asked Daisy.

Mario looked stupefied. "Uh, it's a long story. She's kinda like a magical space princess who is the mother of the Lumas, which are live stars, and she lost her mother, and she shoots through space for like, ever, and she visits her home planet every hundred years. She's real mysterious and monotone." He finished.

"Uh-huh." Daisy replied.

Mario sighed. "Hopefully we'll have time to—" he was interrupted by the ringing of the doorbell. "Oh, great, she's already here. Lovely."

He went to open the door but was blocked by Luigi. "I think it's about time I was the one who answered the door. You've answered it the past one hundred twenty-three times it needed answering." With that he opened the door.

Purple Toad the Mailtoad stood there. "Here's a letter for Mario." He said.

Mario took it. "It's from Rosalina." He said. "She says she'll be here in an hour." Purple Toad left. "So, what do we do to prepare?" Mario asked.

"The whole house is already clean," Luigi replied. "I guess we can just sit around."

An hour later, the doorbell rang. Mario answered. Rosalina was standing there with Polari.

"Hey Rosalina, what's up?" Mario asked.

"Space travel, the usual," Rosalina replied.

"Uh, I'm sure you remember Luigi and Peach," Mario said.

Luigi and Peach stood there. "Hi." Luigi said. Peach just waved.

"Of course," Rosalina replied to Mario.

"Oh, and, uh, this is Daisy," Mario said.

"Hi," Daisy said to Rosalina. Rosalina waved.

"So, uh, I figured we could go swimming!" Mario said.

"Sounds good to me!" Luigi answered.

"What about you, Rosalina?" Mario asked.

"Sure," she replied.

"Okay, then. Let's take my Mercedes out back." He led them over to a silver GLA. "Rosalina can sit in the front."

He got into the driver's seat. Peach and Daisy sat in the middle. Luigi was in the back. "Let's go!" Mario said, slamming the gas.

In no time they were at some pool. Blue Toad and Yellow Toad were splashing around like an old married couple. Or maybe a young married couple. Who cares?

"Hey, guys!" Peach called.

"Hey, Princess!" Blue Toad called. "Hey, Rosalina lady!"

"Uh, ignore them," Mario whispered to Rosalina. He dove into the pool and swished around.

"Cannonball!" Luigi yelled and splashed into the pool.

Peach and Daisy had to change into their bathing suits. Then they dove in. Rosalina sat on the stairs.

"Too bad Rosalina doesn't have a bathing suit," Mario whispered to Luigi.

Eventually Rosalina swam with them. After they were done they drove home. They had actually spent hours at the pool, so it was about bedtime when they got home.

"Well, Rosalina, it's been a pleasure," Mario said.

"Goodbye." Rosalina said and stepped outside. A bright, blue light erupted through the windows. They all looked outside to see the Observatory there. Rosalina stepped up on it and waved as it transformed into a comet and blasted off into the starry sky.