A short ficlet set pre-series, based on a small scene in episode 11 of season 4. I just thought there was more to the word's Casey said to Herrmann during the Tornado call than what was shown. So this is my interpretation. You may recognize some quotes in here from the episode itself - those words are not mine, neither are the character. Please don't sue!
Nothing else exists
There was nothing routine about the call. Fathers shouldn't lock little kids in basements and set their home on fire. Mothers, hiding their pain in pills and bottles, should not have to shoot their husband to escape the torment. No, there was nothing routine about the call.
"Candidate, let's do it!" Herrmann looked the young man up and down. There was no outward sign of turmoil, except for an imperceptible shake in his hands and a slight quiver surrounding his maxilla. The young man was fresh out of training, second in his class and eager to please.
Being the father of House 51 (at only thirty-four years old, though few seemed to remember that fact) it was expected of Herrmann to look after all newbies. A task he didn't relish, but completed none-the-less, as his Lieutenant and Chief expected it of him. There hadn't been a lot of time to get to now the young candidate, but from what Herrmann had seen he had a good head on his shoulders, could lead men twice his age and could navigate politics as well as diplomacy like a man that had been raised in the White House.
It therefore came as a big surprise to see the candidate freeze at the order. The call had come in just as they had arrived at the fire house, and details were still busy emerging. The information that they did have indicated a volatile situation, although no more than many others they had faced over the past two weeks the candidate had spent with their House. Three young children were trapped in a basement, set ablaze by their father, who had been killed by their inebriated mother only seconds later. The mom was safely outside of the blaze, already in the hands of PD. The building, whilst highly unstable, should be relatively safe to enter, extract the kids, and kill the blaze, all within a few minutes. Thus the incredulity that the candidate had frozen at a simple order of entering the building.
Knowing that they had little time to spare, Herrmann turned to the candidate and firmly said to him: "Whatever you are feeling right now, I want you to put all of that energy into this call. Nothing else exists."
With a nod and a quiet "yes sir", the candidate followed the veteran's lead, safely extracting all three kids whilst their fellow firefighters swiftly brought the blaze under control. All three children were safe and unharmed, except for minimal smoke inhalation, but were whisked away to Chicago Med for the necessary checks, before they would likely be placed in the hands of child services. The process from extraction to placement on the awaiting ambulances took no more than ten minutes, but during that time Herrmann could see the candidate flagging, before finally taking off at a brisk pace, vanishing behind the edge of the house.
That was where Herrmann found him five minutes later, head in hands, skin ashen. Sitting down gently next to the young man Herrmann softly inquired about his current state. He fully expected a generic "I'm fine" in reply, and as such was surprised when the young man spoke up, barely above a whiper.
"My mother killed my father, and I hate myself for being glad that she did. She's in prison, because she did something which I had wished would happen for most of my life."
"My father, he was never a good man. Christie still hasn't forgiven her, I never thought there was anything to forgive. You must think I'm a monster".
Looking at the candidate Herrmann was rendered speechless, a feat all by itself. For a man who generally looked so put together, to carry such a burden with him, it was unthinkable to Herrmann. Realizing the man didn't need any simple platitudes Herrmann simply gave him a pat on the shoulder and repeated his earlier order. "Candidate, Let's do it! You're going to be fine."
"Yeah?"
"Yeah."
Pulling the young man up, the two men walked side-by-side, one with a million questions raging through his head, the other realizing that he may have finally found a family.