American actor and wrestler, John Cena has revealed that his biggest fear is that he would never be ready to be a “great parent.” The 47-year-old, who has been married twice without kids, explained that he would never be ready to invest the time needed to be a great parent. “My biggest fear is I don’t think I’m personally ready, nor will I ever be, to invest the time it takes to be a great parent,” Cena said in a recent interview with Club Shay Shay. “Because I still have a lot to do and I still want to do a lot. I have a wonderful partner, we’ve had open conversations about this. We share the…