William and Kate are expecting their first child. As the world awaits the next chapter in their story, the greatest unborn celebrity is already garnering global interest. Discovery Channel’s ‘Will and Kate: Baby Fever,’ April 21 at 8 p.m., offers insight into family life in the house of Windsor and the compromises the couple will make in order to raise the future ruler. Whether boy or girl, the removal of sexist succession laws now gives sons and daughters equal hereditary rights and has paved the way for a truly modern monarch. Experts, insiders and historians will look at the childhoods of Queen Elizabeth, her children and grandchildren. They will offer their views on whom the couple will look to for guidance. It will be a tightrope walk for Will and Kate. As modern royals, they have to balance tradition with contemporary expectations, private life with public demands and family values with national duty. There are big questions that all parents face, but which this royal couple must solve.