my ipod password wont work?

[Connor]

You could first try to turn it off and on again then put in all your password. If that doesn't work your sister might have changed the password without you knowing so just ask her nicely once then if she doesn't tell you, just tell your parents(the stricter one) she changed it and if she did she'll tell you then she didn't change it, this may be a little bitch thing to do but if you want to get your iPod back I suggest that you do it, trust me I have a sister of my own
If that all doesn't work then you probably need to take it to an apple store to get it reset, you can see what apps you have downloaded by checking Game Centre.
Hope this helps