Hello, welcome to the board, you've found a great place as you've already seen.

The only thing you can do from here is equip yourself with bible knowledge, JW's or the borg as we like to call them around here have a very effective bible training/brainwashing program in which they know how to answer almost anything by taking most scriptures out of context.

A great sight to check out is freeminds.org. Here's a link about the New World Translation.

http://www.freeminds.org/doctrine/nwt.htm

I would also recommend Witnessing to the Jehovah's Witness by Ron Rhodes, a great counter argument book.

My heart goes out to your sister, and I would strongly encourage her to come to this board to seek advice. Being a non believing spouse can be very taxing on a family. Esp. when it comes to forcing your children to all of the sudden stop celebrating holiday's, having to censure things that were always ok, spongbob! poor kid, and then especially if something should happen and the kid needs a blood transfusion to stay alive, your BIL will be forced to let his child die in that circumstance.

He's only been in six months and already getting baptized! This is a bit strange and sounds like he's jumping blindly rather than willingly. Aparently he may not know fully about their blood doctrine and how many children have willingly let themselves die because of it. Nor does he probably know that their founder Charles Taze Russell celebrated holidays and birthdays and even had the cross on his magazine's.

http://www.religioustolerance.org/witness.htm

Don't go on the offensive, when you hear him preach something, ask him to show you in the bible where he got it from....then politely point out to him how that scripture doesn't seem to follow the context of the chapter or sermon.

When it comes to holidays and birthday's, kindly ask him then why are JW's allowed to wear wedding rings, born of pagan traditions, also allowed to attend graduation parties, a practice started by the Greeks in reverence to their gods, why they don't mind adhering to the calander, since the names of the day's and months were born from pagan gods, go on honeymoons, practice safe sex,(yes it's true, the borg has controll over what married couples do in the bedroom. A few months ago a talk was given and it was about practicing oral sex and how it is a sin....and they openly talked about it in front of all the children in the kingdom hall!)

Anywho....again I would encourage your sister to come here.

Matt