Probably a silly question, but I'm wondering. My puppy just hacked the end off his Nylabone puppy bone (it could be that it's the wrong size - he's had it for almost two months now and he's a big boy). His big sis, 8-year-old Tip, helped him, actually - so maybe he couldn't have done it without her. But anyway - I'm wondering if I should up him to a tougher chew and am wondering if the Flexi Chew is stronger than the Puppy Bone. I'm assuming it is??? Thank you!