thanks for all your kind replies. he's over the kennel cough and fleas thankfully.the vet thinks he might be cold, or nervous or it could be some neurological thing but thats unlikely. i am in park ridge,il so its cold here. he shakes in the house too but much less than outside. i think i'll just give him some time to grow up and quit worrying. i got him from a new breeder in elburn,il. it was her first litter from her dog. she breeds horses and the mama dog is a farm dog so hence the fleas. she let me know he probably had themwhen i got him. the strange thing is his mom was 12 pounds and the dad was 2 lbs. she thought rocky would be 6-7 but he's 16 weeks and only 3 pounds. where do you guys think he'll end up? thanks again. this group is great. i have learned a ton on here. michelle