A west Cork man pleaded not guilty to the murder of his wife and his two sons denied murdering their mother on Christmas Eve two years ago at the Central Criminal Court in Dublin yesterday Mr Joseph O'Brien (48), his sons Kieran (21) and Noel (20), denied the murder of Mrs Julia O'Brien at their home at High Street, Drimoleague, Co Cork, on December 24th, 1995. They also pleaded not guilty to her manslaughter, assaulting her occasioning actual bodily harm and common assault on her on the same date.