Using someone elses p?

i wanna go to kings dominion tommorow, but i dont have a p. my friend shannon was going to let me use hers. we dont look COMPLETLY diffrent, but we dont look alike. i mean, we look like we could be sisters sort of. but she deff couldnt p as me. but i want to use her season p, do you think there really gonna look at it and be sure? and if its not me do you think theyll flip and not let me in even if i say that i accidently grabbed the wrong one or something?