Sometime prior to 2149, he did something horrible to upset his wife Vesna. She hadn't forgiven him by 2152 despite the fact that he'd apologized twice, but Feezal felt she'd forgive him after another two years.
Groznik was Dr. Phlox's first wife's third husband, who together had a daughter named Indaura. While attending to his affairs back home, Dr. Phlox recorded a message to Dr. Jeremy Lucas, requesting that Lucas contact Groznik and tell him that he was welcome to keep an Aldebaran drum set Phlox had loaned him. (ENT: "Zero Hour")