United Kingdom, Aug. 19 -- Ellen DeGeneres has paid tribute to wife Portia de Rossi in a sweet social media post to mark their 18th wedding anniversary.

The chat show host marked the special occasion with a snap of herself and Ally McBeal star Portia on Instagram, as she wrote alongside it: "Happy anniversary to my favorite person in the entire world.

"I can't believe how lucky I am that I get to spend the rest of my life with you. What an adventure we are having!!"

Ellen and Portia wed in August 2008, after starting dating in late 2004.

The 68-year-old presenter's post was then inundated with messages from the couple's famous friends, including Kris Jenner, who wrote: "Happy Anniversary beautiful friends we love you!!!!"

While Baywa...