John went straight into the kitchen when he returned home from his job at the clinic. He busied himself with putting his shopping away and cleaning the table and the kitchen counters. It was only once he'd finished his tidying that he ventured into the living room. He froze in the doorway at the scene before him. Sherlock was sat in his armchair, perfectly calmly, whilst his elder brother lay on the floor just a few feet away. Drops of Mycroft's blood had stained the carpet
"Sherlock? What the hell happened?" John demanded as he made his way over to Mycroft. He kneeled beside the man and lifted his thin wrist, checking for a pulse. He was relieved when he found a steady pulse and he began examining Mycroft's injuries.
"Leave him, John. He's not fatally injured. He's unconscious due to a concussion." Sherlock said, picking up his violin and plucking at the strings.
"Did you do this to him? Why?" John asked, turning to look at his flatmate.
"Do I need a reason? He's controlling. He needed to be reminded to leave me alone." Sherlock replied.
"Reminded? Please tell me you've not done this before. This is abuse, Sherlock!" John shouted.
"Mycroft is fine. He can look after himself." Sherlock dismissed.
"I'm calling an ambulance. He's bleeding, so that's not a good sign." John said, pulling out his mobile and dialling 999.
"He fell." was Sherlock's lacklustre excuse when the paramedics arrived. They didn't believe him but were more interested in rushing their patient to hospital.
John was surprised when a bruised and battered Mycroft arrived at 221B just four days later. Sherlock had been calm but had refused to tell John about the attack. "How are you feeling?" he asked.
"Better. It was quite a fall I had." Mycroft replied, limping slightly as he moved to sit down.
"A fall? You didn't fall and you know it." John said, watching the elder Holmes brother.
"My memories are a little blurred due to the concussion." Mycroft replied as an explanation.
"Has he done this before? Hurt you, I mean?" John asked, trying his best to sound reassuring and friendly.
"I have no idea what you're talking about, Dr Watson." Mycroft said, wearing his usual mask of indifference.
"What are you doing here, brother?" Sherlock asked, walking out of his bedroom and into the living room.
"I brought stain remover with me, to clean the blood out of your carpet." Mycroft replied, holding up the spray bottle.
"Good. Get on the floor and start cleaning." Sherlock said, challenging his brother.
Mycroft didn't move for a few moments, holding Sherlock's gaze. With a sigh, he slipped off his suit jacket and moved to kneel on the floor. He sprayed some of the bleach onto the carpet and used his handkerchief to scrub at the bloodstains.
John stood and watched, genuinely shocked that the government official was cleaning his own blood from the carpet. "Mycroft, you don't have to do that." he said.
"Yes, he does, John. It's his blood." Sherlock replied, "A little manual labour won't do him any harm."
John frowned, looking between them. He didn't understand the strange atmosphere that filled the room. It was obvious that Sherlock had attacked Mycroft, but he still didn't know the context behind it.