I'd say... don't worry about your sister right now. Don't worry about it. Your sister is her own person, capable of finding her own way. Perhaps her way simply isn't your way.
My first inclination was to say worry about yourself - but don't worry about yourself either. Give yourself fair time. Just.. put 'knowing' and 'truth' on hold for a bit... don't be too greedy with understanding. Be ready to come to know it over time.
Instead, I'd suggest (and feel free to completely ignore this, I'm just a 30-year old) that you not worry about anything but instead just ask questions right now - all the questions you weren't allowed to ask or consider. Then find the answers - even if sometimes the answer is "we (humans) don't know." Read everything you can, watch documenteries... on the bible, science.. everything - and question it all. Question everything, do research on things until you are satisfied that you've either found the answers, or are reasonably confident that we just don't know yet. Sometimes the most honest answer is that we don't know.
When I first left, I felt very challenged... that by default, I was the one that was wrong, and that I had to prove it. I don't feel that way anymore. I don't care if my family doesn't want to change. The important thing to me is - I changed. I overcame cult indoctrination, and I am proud of myself for that.
The truth has literally set me free - not 'absolute' truth - but just honest, simple truth. We know some things. We have very strong theories on some things. We don't know some things. But no man, no "pope"... no governing body (aka "group pope") tells me they are the voice of some supposed god that knows all... and proves it by acting like a chicken with it's head cut off.
My family has learned not to talk about it around me. And when they try to 'hint' or be 'encouraging', I call them out on it, and watch their faces turn red. I ask them if they want me to 'hint' about the accuracy of various radiometric dating methods. I ask them if I want a quiz on just where creationism and evolutionary biology fails? Just how well versed are they on both topics? If I ask them just what are the 'gaps' in our understanding of evolutionary biology... what will I tell them when they guess wrong? Or should I 'hint' at the inaccuracies of the bible or their beloved governing body and it's failed prophecies?
To conqure them.. and to know and conqure their doubts - knowledge is the key. Knowledge is the power - and not just the 'cheap' hearsay from here, youtube, etc.. but real in-depth knowledge. The kind of stuff your average JW is too lazy to seek... and completely obliterated by.
I know your pain... I hate to see my brother and sister waste their lives for the WT. But ultimately... that is their choice. We all choose our own paths. Perhaps it's just taking them a little longer to realize that the milk is sour. My family is inheriently introverted and fearful - they are all equally comforted by the WT teachings - free from personal responsibilty to challenge their genetic dispositions. Still, I have a feeling that before all is done, perhaps my brother, my father, or my sister will see the faulicy of it all. They are all so taken in by the idea that any matter of faith is superior to that of knowledge. It can be very challenging - my brother literally attacked me just for my respect of education and desire to someday have a degree... but I can tell they all hold their doubts. Sometimes people need to see something - and that sometimes takes time. For me, it was a real wake-up call to hear my ex-wife's personal accounts of her sexual abuse and subsequent visits to the elders as a child.
Anyway, for your part... I say just be glad that you are free. You won. You are free. You can't change other people... just tell them what you think and let them see that you are a person.
- Lime
