acting with other dogs

Question
i have a 12 week old shepherd and a 2 year old lab. they seem to get a long fine. but at times the shepherd seems to get mean with her. the shepherd is a boy the lab. is a girl. they start to play and he starts to nip her near the chest. i cant really tell if she likes it. i cant tell if he is playing. i dont want this to be a problem when he grows up and will be able to over power her. when i tell him to stop he dose but then he stops playing with her. and i dont want that. i want them to get a long. the lab dose not have one mean bone in her body. i want him to be the same way. i had him for about 3 days now he knows how to sit and give paw and is starting to go to the door when it is time to go outside. he catches on to thing fast. i just need a pointer or two. to hel me to stop him nippen my lab. if you could help me that would be great. thank you for your time. and if u have any info or articles on shepherds it would be great if u could send me some

Answer
Hi  chris
Sorry so late, computer crashed and just loaded this new one up today.
First of all Shepherds well bred are not mean and nastey, I breed the pure West German Lines from Germany, highly intelligent, lovable, socialble, bonds quickly, loyal and learns fast and gets along with anything in the home.
I just sold a litter of nine into home with other dogs, cats, birds, all send me praises of the pups intelligence and easy to train etc.
go to www.dogsbestfriend.com and buy the monks from new sketes video or book they are very good.  Look on my site on front page at the video or click on email on litters page and I can send u training videos Dr Ron my mentor and best friend that bought a pup from me last summer has trained in basic obedinece that might help you also.?
The Shepherd is a puppy I have no idea what lines she has or where u got here but if she is well bred for top lines, she will learn to adapt and love the lab as her friend, not get mean and hurt the lab,now she is playing as  a puppy will and just let things be.
Be positive in training and disapline and not negative at al, never hit a puppy nor be mean for it will make it worse, be positive and talk like they are your children, raise your voice and mean what u say and be firm and be the leader and boss of both, your the dominant one now or they will take over and get in charge and your done.
visit my playful page of my dogs, my video i made today the ninteen of feb with my dogs all together with Gino the stud I use from Germany.
You must be boss and leader to teach right from wrong, click on email on litters page and I can guide u better than on this site.

Kind Regards
patt
WWW.SCHREKNHAUS.COM
LITTERS, males, playful page, etc.