Okay, Mandy........you're probably starting to scare the others. I'm not scared, I've been posting in this forum almost every day for three years. Except when I go on vacation, have surgery, or during final exam crunch time.
Couple of questions:
1. How will you decide what type of master each guy that becomes jedi gets? Will it be random, will you decide according to the profile or what? If you want to keep it secret, feel free, I'm just wondering.
2. Will you include specialization training? Like maybe once you become a soldier you can become a sniper, etc.
3. How will you handle piloting? Will there be seperate training for that, or will it just be a part of all training, since jedi and soldiers are probably trained to fly
4. Will there be any side-skills, and how will these be handled? Stuff like negotiating, Hacking, etc.
Vader's wife was very pregnant when she died 19 years ago. All of a sudden a 19 year old who is very strong in the force and has a distinct resembalance to him in his younger days rolls in from Vader's home planet with his old Master Obi-Wan (Who was the ONLY other person preset at the time his wife died. And to boot, the kid's last name is Skywalker.
So in answer to your question, he knew Luke was his son because his name is Darth Vader, and not Darth Retard.
-Forum post on why Vader knew Luke was his son.