Maybe she'd be less angry and withdrawn if you just talked to her instead of snooping? My mam once gave me money to buy a diary with a lock on it once because she thought writing would make me feel better and that I should be able to write without people looking at it. If she had genuine concerns, she'd try and get me to talk and hand me leaflets, books and phone numbers for things like Childline and the Samaritans so that I'd have someone to talk to if necessary. Throughout my high school years, I had all these little information booklets on depression and drugs and sex even though I was actually perfectly fine. I appreciated the effort she went to to make sure that I wasn't alone and that I had some sort of safety net, but I appreciated her respect for me even more. Because she respected me, I was more likely to go to her with my problems.

I'm betting that the 100+ thumbs down on the first comment "parents have more right to snoop though their kids stuff" we're by children...No, we didn't like it any more as kids than you do...yet it is true that we have the right, since we are responsible for you until you're 18...so for those who thumbed down #1, just you wait until your child is doing stupid things or gets pregnant, in jail, commits suicide & people all look @ you & think.."what a shitty parent" you are for not knowing what your child was up to & how it could have been prevented if you had snooped.

Your just being a concerned sister. I would have done the same with my sister, she's my everything and we've been through alot.

Who still has a diary? Is that a common thing these days?

Next time, don't get caught, and make copies for proof of what you read.

Uh huh, you were worried hmm? :) Ok. (I woulda done the same thing)

Do as I say and not as I do.... Only joking that sucks OP, I hope you sort it out with your sister though xx

Why not just talk to her? That's likely already BEEN tried and reading through the diary was a last resort. I say FYL, especially for your mom being a hypocrite

While what you did certainly isn't okay, your mom is a giant hypocrite. And I can certainly see where you picked up that behavior.

Wow, why couldn't you have just talked to her about it? Maybe she was angry and withdrawn because Mother Nature came for a visit or it's a hormone thing. You know how it feels to have your privacy invaded. I bet that made you mad. So how would invading your already angry sister's privacy make her any happier? Also, I think it's kinda funny OP worded this post to make it sound like "checking" her sister's diary is perfectly normal. Like "Oh my sister slammed a door and won't talk to me. I better look in her diary for clues while she's in the shower! I just won't tell her. I don't need to, it's for her own good". Because obviously, that's what real psychologists do, they sneak into their clients personal stuff instead of asking. I also want to know what stuff OP's mom went through. Like was it reading her diary too, or was she just organizing her sock drawer which just happened to have her diary in it?