Lily was born in Vietnam on February 19th, 2008 and was adopted as a baby by Mitchell and Cameron. When she was in the orphanage at Vietnam, she was raised by a group of Asian women as shown in the episode "Fears".
Mitchell originally wanted to wait to tell the extended family that they had adopted Lily. However, Cameron knew Mitchell will shy away from introducing her forever, so he plans a surprise dinner where he introduces the baby in a Lion King manner. The family welcomes her with open arms, even Mitchell's dad Jay (who can seem a grumpy character at times especially when it comes to Mitchell and his, what he calls, 'gaydar' (radar for homosexuals)). She is, at times, doing activities with both of her fathers, but remains with Cam at home while Mitchell works.
Cameron often dresses her up as celebrities, such as Diana Ross, Madonna, and Ray Charles for the purpose of taking photographs. Cameron and Mitchell are currently practicing the Ferber method on Lily but Cameron can't always resist catering to her during the night, sometimes even watching movies such as Scarface, which Cam claims she likes possibly because of the bright colors, particularly the club shooting scene.
Another noticeable thing about Lily is that in most episodes she appears in she is seen with "Doggy," her stuffed dog, which appears to be a Labrador. She is a quiet and peaceful baby when portrayed by infants Ella and Jaden Hiller, and does not speak for the first two seasons.
Lily is no longer played by babies Ella and Jaden Hiller, but instead by bubbly preschooler Aubrey Anderson-Emmons. She now begins to talk and becomes a full-fledged character. She is vocal about not wanting a new baby brother, and is shown to have some other faults typical of toddlers, such as difficulty with sharing.
Mishaps with Lily
There have been several occasions in which Lily has been involved with and/or caused a problem during an episode.
In The Bicycle Thief Lily seems behind, so Mitchell "steals another child's intellectual property", as he puts it, before realizing all play dates are recorded.
In "Hawaii", during a Hawaiian vacation, Mitchell and Cameron get into an argument that continues when they leave the elevator– and neither of them pushes the baby carriage out with them. Luckily Gloria finds a run-away Lily on the first floor.
In "Run for Your Wife", Cameron has finally convinced Mitchell to dance with Lily. But Mitchell accidentally hits Lily's head on a door jamb when he throws her up in the air. After quite a bit of fussing, more by her fathers than by herself, Mitchell and Cam finally decide to take her into the doctor. It turned out Lily was fine, but it wasn't long before the next little incident occurred.
In "Planes, Trains and Cars", Mitchell and Cameron lose Lily's favorite stuffed bunny on the subway. She keeps Mitchell and Cameron up all night and they try to tell her that her bunny went to a magical land and to sleep with a different stuffed animal. That doesn't work either.
In "Little Bo Bleep", Lily discovers that cursing (particularly using the F-word) can elicit laughter from her daddies, so she repeatedly drops the F-bomb as Cam and Mitch try to teach her not to say it. The episode culminates with Lily loudly shouting the F-bomb while she is a flower girl at a wedding.
In "Disneyland", it is revealed that Lily is a "runner". Cam and Mitch try to keep her from straying from the family but it is to no avail; she dashes off at every opportunity, much faster than her daddies can catch her. Finally, Cam resorts to putting a leash on her, though Mitchell can feel other parents judging her. Their parenting problem is solved when Jay buys Lily a pair of baby high heels, in which she has no choice but to walk her way along slowly and carefully.
In "Party Crasher" she is shown to be favouring Mitchell and Cam goes out of his way to win back her affection. She is accidentally injured several times in this episode by Cam.
In "Career Day" Lily waits up for the tooth fairy and causes Cam to accidentally leave her quite a bit more money than he planned. Cam and Mitch pull out all the stops to get it back.
In "The Future Dunphys," Lily announces to her parents and Gloria that she is gay because she thinks that since both of her parents are gay, she is automatically gay as well. Later in the episode, it is discovered that she says this because of her desire to be more like her parents.
Lily is a hilarious, entertaining and (physically) charming character with a sassy personality. In "Little Bo Bleep" Lily is heard saying the F-word, solely for the purpose of making her father (Cameron) laugh hysterically. Lily quickly picks up on words or phrases said by other people, including from her aunt, Claire Dunphy. In the episode "Fulgencio" Lily repeats snarky and sarcastic lines originally said by Claire, who had been spending time with her.
- In the Greek adaptation of Modern Family, Lily is portrayed as a British girl rather than a Vietnamese girl. Also, her name remains the same.
- Lily is apparently named after Cam's family pig, as revealed in the episode "Leap Day".
- In the original series and the Greek series, Lily has recast in both versions.
- In the Chilean adaptation of Modern Family, Lily's counterpart is only left with Mitchell and Cameron's counterparts while her mother has left to travel abroad.