"They stood there for a moment; their thoughts and actions, as unwitnessed, where never to be remembered. Then Sirius went for the toy again with one hand, his other one still hostage of the baby; the fingers that were curled possessively around the plush animal unclenched immediately, allowing him to pull it out triumphantly – and promptly drop it with indifference."  Where Sophie smiles and Sirius gets a toy. Baby friendship. One-shot.