I'm sure someone else has already typed an answer to this, but post as well so you can get your answer quickly. You get Lucky Jack Russel by selecting that you lost your parents to a shipwreck at character creation. He will then show up when you run through the Presidio instance. The different companions you get as a result of that answer are as follows:
Mutiny! = Dead Mike (Undead Pirate)
Shipwrecked! = Jack Russell (Dog Pirate) Armada! = Gaspard de Vole (Guinea Pig Guard) Storm! = Milo Greytail (Rat Brigand) Squid Attack! = Birgus Latro (Crab Thug)
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