Melbourne:  Greg, 54, killed his 11-year-old son at cricket practice was mentally ill and had five warrants against him. Luke Batty,11, was beaten to death with a cricket bat  by Greg in front of stunned onlookers after training with his junior team on Wednesday evening at Tyabb oval, 100 kilometres (60 miles) southeast of Melbourne. Greg  was the subject of an apprehended violence order (AVO), which was taken out by the boy’s mother Rosie according to media reports, but it allowed him to visit the boy at his cricket training.