Aggressive Dachshunds?

My mom's dachshund has a mean and violent side that is getting worse. He attacks the other dogs in her house and will not stop until he is seperated..sometimes these attacks are unprovoked. It attacked our puppy twice and they were getting along just fine. The last time it nipped me in the hand when I pulled it away. I scolded it and cleaned the bite wound. 2 weeks later it attacked my husband and bit his hands really bad when he tried to get it off him. We had to go to the ER and get stiches, shots, and later antibiotics because it got inflamed and infected. He is obviously beyone pissed off and feels this dog should be put down because it is nuts..honestly I do too but it's not my dog and my Mom refuses to put down her "baby". It is no longer allowed at our house and we do not visit unless it is locked in it's kennel. Has anyone had/bene around one this crazy??? Is it imbred or something??