Yo ho ho ... and a bottle of MGD ... 'twas a pirates life for Mildred Baena -- who decked herself out as a sexy swashbuckler for a Halloween party 1 year before she gave birth to Arnold's love child.
According to the time stamp on the photos -- the Halloween boozefest went down back in October 1996.
Shiver me timbers!!!
Arnold's Baby Mama
One Naughty Little Pirate
5/18/2011 10:10 AM PDT BY TMZ STAFF
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