Merrill has one brother, Dr. Glenn Markoe. He works for the Cincinatti Art Museum.
Merrill left Late Night With David Letterman because it was putting tremendous strain on her personal relationship with Dave. The two were living and working together at the time.
Merrill appeared in the 2005 movie The Aristocrats as herself.
In 2007, Merrill was a finalist for the Thurber Prize for American Humor.
Most of the charities that Merrill supports work with animals. Her top five causes are: The Jane Goodall Institute, Tails of Joy, Best Friends Animal Rescue, The Humane Society and PETA.
On August 24, 2007; Merrill appeared on National Public Radio's This American Life to read her monologue "Divorce Is Rrruuffff!"
Merrill has released six books:
How to Be Hap-Hap-Happy Like Me
Merrill Markoe's Guide to Love
It's My F---ing Birthday
The Psycho Ex Game (with Andy Prieboy)
What the Dogs Have Taught Me
Walking in Circles Before Lying Down
Merrill: (on the Morning Show with David Letterman) It was live, and great, weird things happened.
Merrill: I spend my life in dread of my obituary, which is gonna say, 'Letterman's ex, creator of Stupid Pet Tricks, dies.'
Merrill: (about working for David Letterman) It was a job I would never take again as long as I will ever live. The reason I ever did it at all was the love affair with the host. There was no growth. It was kind of a sidestep into Merrill Markoe, Love-Chump.
Merrill: (about her dogs) They're all naive good intentions. They're totally non-judgmental. I'm so popular amongst them! They love me with no stipulations. It's really very touching.
Merrill: Some people know that they are so adorable looking, all they have to do is smile and dress up and they get plenty from that. Then there are some of us who, early on, see that that doesn't work. So we joke about it.