"How is she?" Twilight asked.
Nurse Red Heart placed a hoof on Pinkie's forehead. "She's fine. She had quite the panic attack. I've given her something to calm her, but what made her get this way? I've known Pinkie for years and she's never had anything like this happen to her before. It seems rather impossible for somepony like her."
"Well, my brother told me that her brother was coming to visit-"
"Wait. Pinkie has a brother?" Red Heart furrowed her brow. "Funny, she never mentioned that."
"She never mentioned it to me either. Not in all the time I've known her. I know all about her mother, father, and sisters, but never about her brother." Twilight looked at Pinkie, who was sleeping soundly and sucking on her hoof. "I'm going to go back to the library. There's something that I need to know-"
"Wait. Wait, wait, wait. You know, now that you've mentioned it, there is something..." Red Heart stood up and walked out of the ward.
Twilight wasn't sure what to do, but something told her to wait. It wasn't long before the nurse returned with a really old, really dirty envelope in her hoof. She placed it on the table in front of Twilight carefully. It looked like it would fall apart if she breathed too hard onto it.
"What's this?"
"Many years ago, before I moved here, there was a... problem with a creature from the Everfree. Apparently an ursa major had managed to find its way outside and for some reason there's reports of a platoon of Border Guards that came here and killed it. Two ponies died that day. It has become somewhat forgotten over years, but this is the report by the Guards who were here."
"How long ago?"
"Look at the date."
Picking up the envelope, Twilight carefully removed the report. The first thing she noticed was the names of the deceased ponies. One was Misty Meadows, the other was Ruby Flame. The two mares stared back at her with neutral expressions. They seemed to want to tell her something. She felt sad for them. They had given their lives protecting others and they were unknown to the local populace. The entire event took place over six years before.
"What's this got to do with Pinkie?"
Red Heart pulled up a seat. "Well, let me tell you how I came across that report. It was late one night and we were moving some files from the old documentation room to the new one down the hall. So, we had to resort through all the files. When I was going through them, I had to redo some where the paper was almost gone. This hospital is almost as old as the town itself, so some of the records were almost destroyed, but then I got to a part where two years were completely missing. So I asked Dr. Stable what happened to them."
"And?"
"He said they were destroyed. Apparently that ursa I mentioned had destroyed the old portion of the hospital. That's why the entire eastern wing is a lot newer than the rest."
"I've never noticed."
"Well, that's earth pony ingenuity for you. Anyway I had to put the files in chronological order, so I had to look at the dates. After the missing two year gap, that was the first report. I've kept the original aside... I've been meaning to send it to Canterlot, but haven't gotten around to it."
Twilight looked at the reports again. She read the names and the ranks. Corporal Misty Meadows, and Warrant Officer Ruby Flame. Both had the letters KIA below their names.
"What's KIA mean?"
"Killed in Action."
Setting the reports down, Twilight looked into Red Heart's eyes. "What's this have to do with Pinkie?"
"Read the reporting officer's name."
At the bottom, written clear as day, was the name: Semper Pie.
"Wait. Semper's been to Ponyville?"
"Oh, so this is her brother."
"You've never brought this up with her before?"
"Of course I have, Twilight. But Pinkie denied having any brothers when I met her, so I never pressed it. After all, who would forget their own brother? Unless..."
"Unless?"
"Unless something terrible had happened. Something so awful, that it traumatized her."
Twilight remembered reading something like that. "So... she made herself forget?"
"Yes. If something is so awful, the mind will purposely block it out. If something ever reminds that pony of that event, it could trigger negative emotions. Most common of which is-"
"A panic attack."
Red Heart nodded. "I think that if you want Pinkie to remember, you're going to have to confront whatever it was that made her forget it in the first place."
"Her brother is coming here-"
"He is? Oh. That's not good. That's not good at all. If whatever triggered her attack is associated with her brother, then her seeing him might be very bad."
"How bad?"
Red Heart's silence spoke volumes.
"Oh. I've got to tell Shining to convince Semper not to come!" Twilight stood up.
"Too late," a voice said from the door. Shining was standing there. "He's already on his way."
"Then we need to warn him!" Twilight insisted.
The two of them looked at each other. Then their eyes grew wide as they reached an epiphany. There was one way to get a letter to him quickly and reliably.
"Spike!" the both exclaimed together.