Jake Gyllenhaal, son of Stephen Gyllenhaal, plays Donnie. His real life sister, Maggie Gyllenhaal, also appears in the movie, as Donnie’s own bickering sister.
“We definitely had a little sibling rivalry” Jake says of the spectacular dinner table slanging match “especially as she is older. We’re brother and sister; we do fight like that. We don’t call each other fuck-ass though”
taken from DAZED AND CONFUSED
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