Solved.

Set a couple of months after the trial

As Sherlock sat, waiting for Joan, he thought about the past couple of years. His relationship with Joan has gone from strength to strength, sure they've had their moments but what couple hasn't? He has a beautiful baby boy, who he adores so much and his relationship with his father has gone from none existent to rebuilding. And now he's here.

'Sherlock?' He snapped out of his trance. 'You ok?' He looked up to see Joan standing with Joesph.
'I'm fine. Just thinking.'
'What about?' She sat down susunod to him.
'Life.'
'Sherlock..' She took his hand in hers. 'It's...

Sherlock woke the susunod morning, Olivia was lying asleep beside him. He got up and went downstairs, no sign of Oscar or Micheal. He took out his phone and dialed Joan's number.
'Sherlock.'
'Morning Watson.' He heard Joesph in the background. 'He's up early.'
Why do you think i'm up?'
He laughed.
'I miss you.'
'I miss you too.'
He took a deep breathe.
'I have to tell you something.'
'What?'
He looked out the kusina to make sure Olivia wasn't up.
'I've figured out a way to get closer to Micheal.'
'But?'
'But it involves me and Oscars sister.'
Joan went silent, she held the phone against her chest imagining...