John's trying to make a cup of tea. Not a difficult task under normal circumstances but, well, when is anything ever normal when Sherlock's involved.

'Where have you put the teabags?' he calls when five minutes of searching prove fruitless.

'I threw them out,' Sherlock says absently, wandering in from the living room clutching a large book entitled From Alpha to Omega: The Ultimate Guide to a Perfect Gestation.

'Do I want to know why?'

'Caffeine. You can't have any.'

'Sherlock, I'm a doctor. I know what I can safely consume. One cup of tea isn't going to hurt me.'

'Too risky. You're mature for a primigravida as it is.' He points to a box behind the steaming kettle, 'I got you ginger tea instead. It's good for nausea.'

John refrains from saying that he's suffering from exhaustion, not morning sickness, reminds himself that Sherlock means well and pulls open the crockery cupboard.

And then he closes his eyes briefly and prays for strength.

'And I suppose there's also a perfectly logical reason why the mugs are hidden behind … two dozen brands of pregnancy supplements?'

Sherlock looks at him with what can only be described as his "How do live with your stupidity?" expression. 'Of course. They're for analysis. Do you really think I'd let you ingest anything but the best?'