Prince Philip died aged 99 and he was laid to rest in April earlier this year.
Finding Freedom has been updated since its publication last summer with a new chapter.
HarperCollins said the update will also include Meghan’s “emotional healing journey from losing a child to the birth of their daughter”.
Watch: Harry and William blew hot and cold with Charles, claims Finding Freedom book
HarperCollins added: “Behind the scenes of Harry and Meghan’s ground breaking interview with Oprah, details behind the couple’s move to California (and) the various philanthropic and business endeavours the Sussexes have been involved with since their move and what’s to come with Archewell Productions.”
It added: “The continuous challenges the couple face regarding privacy and the British press (and) the heartbreak the couple felt over Prince Philip’s death.”
Omid Scobie and Carolyn Durand have updated the book and the new version will be available on August 31.
It comes as Harry is to write an “intimate and heartfelt memoir” and has promised to give an “accurate and wholly truthful” account of his life. It will come out late in 2022.
In a statement released by publishers Penguin Random House, Harry said: “I’m writing this not as the prince I was born but as the man I have become.
“I’ve worn many hats over the years, both literally and figuratively, and my hope is that in telling my story—the highs and lows, the mistakes, the lessons learned—I can help show that no matter where we come from, we have more in common than we think.
“I’m deeply grateful for the opportunity to share what I’ve learned over the course of my life so far and excited for people to read a firsthand account of my life that’s accurate and wholly truthful.”
Her addition comes seven weeks after Lilibet was born in Santa Barbara, California on June 4.
Harry and Meghan live happily in Los Angeles with their two children Archie and Lilibet.
Watch: The Queen's Biography