Of angst and cradle snatchers...
Some excellent fics exploring the Remus/Tonks relationship within the context of a history of Remus/Sirius.
profcricket wrote Life During Wartime which gives amazing insight into the pairing while the entire piece is haunted by the memory of Sirius.
topaz_eyes wrote Missing - a sensitive and profound picture of their being together while still 'missing' something.
And minnow_53 wrote Cradle Snatcher which is a brilliantly hilarious take on the scenario!