My daughter recently had a miscarriage. Her immediate boss was informed and a doctors note was provided. Upon her return to work all her co workers including new hires she had never even met knew about his situation. Is this a HIIPA violation?

She should definitely consult someone in the human resources department at her work to see what couse of action she needs to take, there was a violation to her privacy in this instance.

I don't think you can prove HIPAA violation, just very bad judgment on her boss's part letting someone know who was a blabber mouth.

Tick

... Is this a HIIPA violation?

No. HIPPA doesn't apply to employer/employee situations.