My older JRT is biting our children and friends

Question
We have an older JRT Roscoe that has been a great dog with the usual JRT attitude of being fun and tough as well as loving. He is now 12 and has begun aggressively taking food from the kids as they eat and biting them on the hand. Roscoe has always barked at people as they leave our home but now he is biting the ankles of all the people who leave the house. Kids are now afraid to come to our house and he just bit our oldest son badly on the hand. What can I do ? Is this common? I do not want to do you know what, but I can't have this be the daily activity of the dog.
Please advise.

Answer
Hi Ed,

You should take Roscoe to the veterinarian and have him looked at. Usually if a dog is in pain they will act out aggressively. He is also getting up there in years and could be experiencing some grouchy personality changes (grumpy old men)! Like people, the brain chemistry changes over time. I would go to the vet and first rule out anything physical. I don't blame you for not wanting this to be the "usual" behavior for the dog, and you have to do what is best for the family and children first.
Good luck!