I've only seen bits of Holby City so I hope I haven't got Bernie's character completely wrong, but the plot bunny bit so I had to write this (I'm such a hurt/comfort junkie).

My theory on the names based on Doctor Who canon - both of them changed their surnames so they could have their military careers without the influence of their father. Whilst Kate just dropped the Lethbridge, Bernie changed it to a variation of her childhood nickname (Kate was canonically called Tiger by her dad so Bernie being called Wolf would fit the theme). I've read other Holby City/Doctor Who crossovers where Kate calls Bernie 'Wolfie' which I loved so much I included the nickname here.

It was the incessant, rhythmic beeping that Kate Stewart was first aware of as she started to wake up. Second was the smell of antiseptic and bleach itching at her nose. Third, as she fought her way through the fog of sleep, was the vague feeling of pain radiating out from her left side, but was distant and disconnected, as if the pain belonged to someone else.

She blinked open her eyes, confused to be staring up at a strange white ceiling far above her. This was not her bedroom. Where was she?

The beeping started to speed up as she struggled to lift her head, automatically trying to search for danger. There was movement to her right, a figure standing, and she flinched away, pain suddenly spiking from her side.

The figure moved closer and sat at her pain free side, hands restraining her shoulders.

"Easy, Tiger," said the figure in a calm and soothing voice. "You've been banged up quite a bit." Kate tried to focus on the face of the figure and was surprised to find it one she knew. There were only two people in the world who called her Tiger and one was her late father.

"...Wolfie?" It was Bernie, her twin sister. What was she doing here, wherever here was?

"Hi Kate. What have you been up to this time?" Kate relaxed back onto the bed, the beeping slowing once more, and looked around, trusting her sister to keep her safe. She was lying in a bed, attached to several machines and she had an IV line snaking out from her left forearm. Either side of her were blue curtains, blocking her view to the rest of what she assumed was a ward. It was quiet and the lights were dimmed. Bernie, sat on the bed next to her hip, was wearing dark blue scrubs and her blond hair was a mess, as per usual.

"Where am I?" She asked.

"Holby City Hospital, Trauma Unit. Do you remember what happened to you?"

"No. I…" she paused and tried to get her foggy brain to cooperate. "Bernie…?" Kate reached out towards her twin, seeking comfort.
"It's ok," said Bernie, taking her sister's hand and rubbing the long fingers with her own. "The morphine is making you confused."

"Was there an explosion? I think I remember fire, and then pain." Bernie nodded in confirmation.

"You had the worst injuries out of the five that were hurt. You had a piece of shrapnel lodged in your side but surgery got it out. You'll be as good as new in a few weeks. The others were all left with cuts and bruises, nothing serious. Osgood told me the basics of what happened, once I managed to persuade her that I did have the right clearance level, whilst you were in theatre. She'll fill you in with more detail in the morning."

"Osgood?" Kate suddenly remembered that her faithful scientist was at her side just before the explosion hit. "Where is she? Is she ok?"

"I managed to persuade her to have a nap in the on-call room, she was exhausted. After being patched up in A&E she refused to leave your side." A sly smile spread across Bernie's face. "Is there something you haven't told me about the two of you?"

"Wolfie, we are just colleagues and good friends." Kate pauses, a warm smile spreading across her own face. "Although there certainly is potential for more."

"So why haven't you done anything about it. You both obviously have feelings for each other."

"We've been too busy. Though after this perhaps I should make the first move."

"Make sure you do. Don't make me pretend to be you and ask her out. I still haven't got you back for doing that to me when we were 12. I would have asked Jenny out eventually!"

"No you wouldn't, Wolfie. You were always a bit shy when it came to feelings. Remind me how long it was before you admitted your feelings to Serena?"

"Too long, I get it. Just don't don't make my mistake with Osgood."

"I won't. I'll drag her into my office by that darn scarf and I'll tell her." Bernie lets out a surprised laugh.

"Kate, you're too doped up to be having this conversation. If I keep going you'll probably tell me stuff you'll regret when the morphine wears off, if you haven't already!"

"Hmmm, probably." Kate shut her eyes, a smile on her face, overtaken by a floating feeling of calm.

"Go to sleep, Tiger," said Bernie, pressing a kiss to her sister's forehead. "I've got to get back on shift. I'll see you tomorrow." Kate faintly hums back, breaths already lengthening into sleep and hand slackening within the grip of her twin's.

Bernie took one long last look at Kate before leaving, relieved that she was safe, if not entirely sound, then goes back to the rest of her shift.

End.