i think my dentist may have violated hippa laws

there is a bill in my name for dental services my child recieved. that was paid in cash. my question is the dentist has sent the bill addressed to me to my mothers home. she uses the same dentist, but my child my mother and my self have never lived at the same address so the accounts ad addresses shouldnt be associated. i shure they sent the bill to my mother hoping she would pay it. my question is is this a violation of privacey laws. thanks in advance