Filing for Form 8615

Hello everyone. I am a 19 year old who was filing my taxes this year. This is the first time I am asked to file for Form 8615 and I am confused on how to fill it out. It asks for my parents information but I am unable to provide it as they both live outside of the United States and don't have a social security number. Would I instead place legal guardians information? I understand that if I am legally adopted I would, but in this case I am a ward of the state of North Carolina and my older brother has guardianship.