be cause my sis ripped my tickets and passes
If you still have the email you can just re print or use the e ticket
If absolutely all else fails, bring a copy of the receipt you got when you ordered your badge. One way or another, the registration staff should be able to get you sorted out.
Even with your sister destroying your badge you will still have the confirmation email that was sent out to you. If you need it again please feel free to email email@example.com and they can assist you.
and you parents are presumable cool with her basically destroying money? tickets are not cheap.
As long as she doesn't go the extra mile to delete your email confirmation and receipt as well, you're fine.
Even then, if you contact BronyCon support they should be able to do something for you.