Nah, Remus is too young to be the third, though he's also pretty old to be the fourth. Shuffling the timelines a little to let them align so the winds of fate blow his father back into his life would make for an interesting marauders-era AU though... or I suppose the third's crew could have gotten entangled with a time mcguffin like movieverse Lara Croft and only escaped in Harry's time.
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‎noli esse culus
‎noli esse culus