So sorry. One cause of sudden death is a rapidly growing cancer called hemangiosarcoma.
She is the right age and it is very common in our GSDs. Painless tumors grow on the spleen or heart then rupture and the dog dies a rapid death. Normally bloat gives some warning and the dog is in distress but with hemangio, they can just drop dead.
NAPWDA Certified Cadaver Dog
Waiting at the Bridge (italics
=GSDs) (hemangiosarcoma=blue):Grim , Cyra, Toby
, Rainbow, Linus, Oscar
, Arlo & Waggles