Sherlock knew her mother, but sharing grief with Sherlock is awkward for them both at the best of times. Ted is deeply empathetic, and can understand and respond to emotions that Sherlock can only be awkwardly mystified by, so she's grateful to have him by her side, even if she shuts down and shuts him out at various points.

Joan leans against him, resting her head on his shoulder.

"Can I take a nap at your place?" she asks softly.