aggression in a terrier puppy

Question
I do animal rescue and mostly rescue pregnant moms and litters of pups.
They come from the south and are rescued from high kill shelters before they are euthanized by gas chambers.
My question is I have been doing this for over 2 years and have encountered a situation with a pup that has been adopted.. I had pregnant mother who was a Jack Russell mix with beagle.  She has the BEST temperament. She gave birth to 6 puppies. Pups stayed with her until 7 weeks and everyone went home including mom.  One of the families, has been e-mailing me about how aggressive his 11 week old pup is.  He growls at everyone and every dog he sees.  He is even aggressive when he is pick up by the owner.  Owner says it is  stressful with puppy and he even contacted trainers. He say the puppy has a horrible temperament and he wants to return the pup to rescue. He has had the pup from 8 weeks old to 11 weeks old. I had pup from birth to 8 weeks old and pup was very socialized and seemed fine up till about 7 weeks when I noticed a bit of growling but chalked it up to terrier puppy mood.  Any advice??
Carol

Answer
Carol -

First - Thanks so much for the work you do.... If only we rescue folks were not needed any more...

I am not really experienced in raising puppies (in fact I avoid fostering them - They just exhaust my patience for some reason).  Does this person have any other dogs ??

I assume this is not a puppy play growl ??  I wonder about pain...  Whoever has this pup (whether you take him back or not) is going to have to work with a trainer right away... or track down a reputable JRT breeder who could give more advice about puppies.

I think it's hard to get a real feel for this without watching the kid in action or handling him yourself

I'm sorry I'm not more help....

-Beth