After reading this whole thread and the whole moral side to spying I'll go a different route to all of this. GO SPY ON YOUR SISTER!!!!!!!!! As much as humanly possible and use the dirt against her, who gives a flying **** if she'd distance herself further from the family, if you got dirt on her then she'd be at your mercy or learn to not do the **** shes doing on her computer. With all due respect your sister sounds like your typical 15 year old teenage whore with some emotional/angst issues where she feels the need to distance herself from everyone around her, she obviously has problems if she chooses to communicate with people and whore herself out to god knows who online (a little strip show anyone?) rather then do it in real life. I can only imagine that someone in the family must have raped her or done something to her to get her to be this emotionally and physically disconnected from the family. Way to go on the spying maybe we'll see some incest payback here or she'd be willing to talk to the family if you told her of all that you know, great spying on people its fun to get dirty on the ones you love and make everything go to ****, this should teach her not to **** around anymore so with that dirt you have.
Sorry if this seems to be unrealistic and out there but I'm tired and slightly pissed off right now so I wanted to do a 180 from the whole ohhh booohoo he's spying on her he shouldnt and the ohhh boohooo let the cops deal with it **** thats flying around here. Now with the dirty you have then you can make her even feel worse about what shes doing and if she cares to keep it a secret she could be a good girl and give some sucky sucky

or she can beg and plead for mercy that you dont tell thee parental units about what shes doing and in either case you come out the winner. She can please you or you can get her to admit that shes got a problem and talk about it with everyone.
Knowledge is everything and dont ever forget that the next time you spy on a loved one or a GF you suspect of something, it can be your friend if its used properly, used as leverage to gain something you want, or strike fear in those you hate and despise. I love having leverage over people its fun to watch them try and squirm their way out of something and do what ever you want them to or say what you want them to but its even more fun to find someone that can play the same game.

hope you find some words of encouragement from this, your sister has a problem a very BIG one if shes distancing herself from the entire family and calling child services on your folks and spending time online and dates online and hides what shes doing when people come in, I probably cant stress how BIG of a problem potentially this could be especially if shes at or around 14-16. If shes had relationships that went to **** then years from now she can be deeply scarred by it, it will affect the way she thinks, the way she forms relationship, who she loves and trusts and her whole world can go out of wack by the time shes 17 or 18 and she'll just turn to drinking and ****ing guys maybe to justify the way she feels or just for self gratification. Without getting into the whole moral or legal bit I'd bust in as a parent, if I saw her attempting to hide something as I came in I'd ask her about it and if she tells me its nothing then depending on what I'd slap her or have a family member hold her down while I checked what she was up to, if she starts screaming and yelling that its none of my business on what shes doing I'd look her straight in her eyes and tell her its every bit my business what shes doing on her computer, she could be web camming and stripping for god knows who online or helping al quida plan to bomb something. I'd then take her down stairs to the table and have everyone sit down with her, make it like an interrogation until she snaps from the pressure and reveals all of it. Yes its mean, yes its rude and violates every moral and legal means that people on these forums come up with but it gets results. She'd cry and tell everyone I hate all of you and scream and run somewhere but I'd give her a few hours maybe a day and go back up and tell her that it was for her own good, she needs to communicate with the family and if shes not then she should expect her computer be taken away (piss weak punishment) or that she'd get "raided" again over and over and over till she learns to communicate and go from there, monitor her pc without her knowing and see what changes.
Anyways this is more of a rant then anything else, if it helps you out great and if it leads to people whining and gasping at the idea's I've Introduced here then you all need to go outside and get some fresh air because you're taking this whole online forums thing WAY too seriously.
Ohh btw if anyones wondering yes I know plenty of women that were abused in some way as teenagers and end up like **** when they're 18 and I myself loved someone that betrayed me utterly so I have similar feelings to those girls that get betrayed or abused and have a lot of build up angst and emotional problems.
G'night