Sheldon was stood in front of his board. He had been staring at it for about an hour and nothing was resolving itself. He barely heard the front door open.

So when Leonard tapped him on the shoulder, he jumped. He turned around quickly, then froze when he saw the look on Leonard's face.

"Leonard. I take it you have spoken to Pen…"

He never got to finish the sentence, because that was when Leonard punched him.

Sheldon had disappeared into his bedroom without a word to tend his rapidly swelling eye, and Leonard was sat nursing his bruised hand. It never looked this painful in the movies, surely it was meant to hurt the other guy more? The initial rush of adrenaline that had driven him to hit his best friend in anger at stealing his non-existent girlfriend had faded quickly. He felt stupid. He still felt angry, but now the earlier confusion and disbelief were making a strong comeback. Penny and Sheldon? How? The whole idea was just insane. He needed to talk to Sheldon.

He knocked on his bedroom door. There was no answer, but he let himself in anyway. Sheldon was not lying in his customary position. Contrary to all evolutionary principles, he was lying on his side with his back to the door. This was clearly serious.

"Um, Sheldon? Are you awake?"

Sheldon didn't move. "If you are planning to hit me again, Leonard, can I request that you do so on the opposite side of my face, so that at least my bruising will be symmetrical?" He sounded defeated, his voice heavy.

"I'm sorry, Sheldon. I shouldn't have hit you. But I was pretty mad at you! Why didn't you tell me about you and Penny?"

"It was not my decision alone to make. I had to consider Penny's feelings on the matter." He still didn't move to face the other man.

"Oh." Sheldon? Considering another persons feelings? He listened hard to see if he could hear the theme to The Twilight Zone playing in the background. He tried to creep around the bed to get a view of Sheldon's face without the other man noticing. In the dim light from the corridor he could just make out Sheldon's hands clasping something. He squinted. It was white fabric, and looked…fuzzy? Something about the object sent some neurons firing, and something suddenly occurred to him. "So...erm, are you ok? With the…baby… thing?"

There was silence for a minute. Just as Leonard had given up on getting an answer, Sheldon spoke. His voice was flat.

"You know, at this stage of development, the gender of the foetus would have been indeterminate. The fingers and toes would have been developing, however. Fingers grow faster than toes, for some reason."

Leonard felt a little lump raise in his throat. "Erm. Ok? Do you want to talk about it?"

"No."

Leonard started to say something else, then changed his mind. He left, shutting the door softly behind him.

Sheldon lay holding the babygrow. He felt ridiculous at being emotional over such a situation. He tried to rationalise his feelings; after all, a certain amount of disappointment was to be expected over the lost opportunity to give the world another child prodigy. Of course, there was a chance the child would have ended up like Penny, which should have been a cause for anxiety; he remembered expressing concern to Leonard about being unable to love a child who didn't know how to solve the area under a curve. But instead, the thought of his offspring resembling Penny made him feel...good. After all, he loved her, he could love their child.

Oh.

The knowledge was just there, in his head. There was no experiment, no variables, no analysis; just the absolute knowledge that he loved Penny. He frowned to himself in the dark. He wasn't quite sure when that had happened, or what to do with the information. Certainly, he couldn't act on it; Leonard had made it clear that his actions so far had caused him distress, and Leonard was his best friend. Without him there would only be Howard and Raj, and he did not find that idea satisfactory. Avoidance would appear to be the best tactic.

Avoid Penny, avoid the problem.