A DOG trainer lets his six-year-old son don the 'bite sleeve' as a 175lb pit bull attacks - before passing the sleeve on to his TWO-year-old brother. Dark Dynasty K9s owner Marlon Grennan, 31, of New Hampshire, is the owner of Hulk, the star of Barcroft TV’s hit internet series Dog Dynasty. Grennan trains some of America’s most ferocious protection dogs, and has earmarked his two sons Jordan, 6, and Jackson, 2, as his heirs - and says he has no qualms about allowing them to get hands on with the pit bulls. After unleashing Hulk on his father, the elementary schooler put on the bite sleeve to be ‘Hulk smashed’ himself by the colossal canine. And as the training session came to a close, Grennan decided to let Jackson, 2, follow in his brother’s footsteps. Dog Dynasty season 2 is available on Barcroft TV’s YouTube and Facebook Watch pages, with a new episode released every Friday.