My name is Dory!

Dory is 14lbs, of unknown age & appears to be a Cairn Terrier mix. We adopted her from a local shelter, she came from a neglect situation. She is great with other animals, we have 2 cats, and she plays well with other dogs. However, she seems a little overwhelmed by people. We have had Dory approx. 2 mos.. My husband & I both work, so arranged for a pet sitter to walk her during the day. The first 10 days went well, but then she started biting the pet sitter. We have since tried 3 more pet sitters, Dory snaps at &/or has bitten them. She has never bitten me, but she did bite my husband once after he came home from a work trip. Most of the time Dory has a very sweet disposition, so the biting behavior is puzzling, we don't understand her triggers. Since we are now unable to find a pet sitter, Dory is kept in her pen for 11-12hrs while we work. She is mostly housetrained, but has accidents if not kept in her pen when we're away. We are not the right fit for her. .