"Oh, I'm sorry," she murmurs sympathetically. Stomach issues suck, and the medications he's taking can sometimes cause them. She squeezes his hand again to comfort him.

Sherlock watches the exchange, and can understand why Ted wouldn't tell Watson the truth. He wouldn't want to worry her. Sherlock can't blame him; god knows he's lied to Watson tons of times for similar reasons. He knows that it would be better if he told her the truth, but he can hardly interfere now.