The family that mushes together

wins Iditarods.

There are a lot of activities that purport to be fun for the whole family, but apparently running the Iditarod, arguably the Interspecies Ironman Of The Cold Frozen North, really is a family affair. Of the 96 mushers who started off this year [that's a record turnout] and in no particular order:

brothers
Lance Mackey, 1st place [as of this posting] Update: WINNER
Jason Mackey, 39th place
another brother and their dad have run the race too, though not this year

more brothers
Ramey Smyth, 3rd place
Cim Smyth, 15th place

more brothers and their dad
Louis Nelson Sr [dad], 31st
Robert Nelson, 44th
Darin Nelson, scratched

a kid, his dad, and his teacher
Martin Buser [dad], 5th
Rohn Buser [son], 33rd
Sue Allen [teacher], 69th

grandsons of the race's founder
Ray Redington Jr, 19th
Ryan Redington, scratched

married to each other
Jennifer Freking, 56th
Blake Freking, 55th
condolences on the loss of their dog Lorne

married, but not running together
Jim Lanier, 20th
Anna Bondarenko, not running this year

Update: As has ben pointed out in comments, I missed a couple.
another husband and wife, and she's waaaay ahead too
Aliy Zirkle, 21st place as of this writing
Allen Moore, 57th place