Prince William is reflecting on fatherhood. In an upcoming BBC One documentary called "Football, Prince William and Our Mental Health," the prince opened up about his feelings on becoming a father, noting that “having children is the biggest life-changing moment." Throughout the documentary, William speaks to several professional athletes, including professional soccer player Marvin Sordell, who grew up without a father -- a situation William can relate to after his mother, Princess Diana, died in a car accident when he was just 15.