Remus makes a wounded noise, but Sirius can barely hear it over the swirling thoughts in his head. Lily... so scared for her and her son’s life she made contingency plans within her contingency plans, so ingrained into wizarding society yet so willing to leave it at the drop of a hat. What a wonderful, brilliant, magical muggleborn! And yet, despite Mary living—likely she had prepared similar contingencies as Lily—she would not be able to help them find Harry. But Lily had not only asked a fellow muggleborn—fighting the same war as them—to bear witness to her plans, but had also asked a fully-fledged  muggle , who knew of their existence because of her husband and son but could not join their world without their help, who was living entirely muggle by then, her husband gone and her son avoiding contact for her safety.