How is your GSD with all the other dogs she has met? In dog classes? When you are taking her for walks?
What does the breeder say?
Can she be sick?
Absolutely keep the 2 dogs apart while you figure this out.
MACH3 Bretta Lee Wildhaus MXG MJG MXF MFB TQX HIT CGC TC
Glory B Wildhaus AX, AXJ, XF
"How is it one careless match can start a forest fire, but it takes a whole box to start a campfire?." ANONYMOUS