Grudge pranks to play on my sister?

Im 15 and she's 17 and she's terrified of the Grudge!!! Its hilarious...she's also very gullible...so on my ipod, im gonna play the grudge voice thing that it makes with its throat and so she'll here it in the middle of the night and freak out..but i want to do something else too...like block the door so she wont be able to get out...haahahah omg i cant wait...any other ideas??