On-screen relatives becoming off-screen couples is nothing new. One couple that is often highlighted in these instances is the pairing of Hayden Panettiere & Milo Ventimiglia, who famously dated from September 2007 to February 2009. Though, they were probably the subject of a lot of controversy more for their 12-year age gap — when she was 18, FYI — rather than the fact that they played niece & uncle on Heroes.
What’s a bit more rare, however, is when television siblings become a romantic pair IRL. Let’s break it down for you — here are 10 real-life celebrity couples that played brother & sister (albeit, not always related by blood) on the small screen:
Blake Lively & Penn Badgley
Long before Serena van der Woodsen & Dan Humphrey ever met and fell in love on Gossip Girl, her mom and his dad fell in love with each other. However, due to varying circumstances, they didn't stay together.
But, after Serena & Dan started dating (and broke up the first time around), their parents realized their love — and married each other! That means that from Season 3 to Season 5, Serena & Dan were step-siblings (or, at least thought to be step-siblings, as the marriage was declared invalid on the fifth season).
As for real life, everything seemed good and well between the two until September 2010, when they called it quits. They continued to have a professional relationship, though — even getting married on the show! — until 2012.
David Henrie & Selena Gomez
It was late summer 2007, the year Wizards of Waverly Place premiered, when rumors of a romance between on-screen siblings David (Justin Russo) & Selena (Alex Russo) made headlines. While the two never outright said they were an item, it's still believed that the romance was the real deal... for about a month.
Maggie Grace & Ian Somerhalder
On Lost, Maggie & Ian portrayed step-siblings/lovers Shannon Rutherford & Boone Carlyle, respectively, until they were both killed off the show.
When the cameras weren't rolling, the two gave real-life loverdom a try. Sadly, it didn't last. The two reportedly got together in April 2006, but were dunzo the following year.
Chris Pratt & Emily VanCamp
2 years after Chris & Emily met on the set of Everwood, on which they portrayed siblings Amy & Bright Abbott, they began a relationship IRL.
Though they kept their mouths relatively shut about their love, they didn't shy away from kissing each other in front of the cameras.
The two were O-V-E-R soon after the series came to an end in 2006.
Dave Annable & Emily VanCamp
By the time Dave came around, Emily was already an expert in dating her on-screen sibling.
The two met on the set of Brothers & Sisters, on which they were thought to be half-siblings Justin Walker & Rebecca Harper. But, as it turns out, a paternity test proved that they were not related, and the two ended up getting married on the show. They lasted for a short while before eventually calling it quits.
And it seems like their real-life relationship suffered a similar fate. Though they never got married, the two kicked off a relationship in 2007, but called it quits by January 2008.
Jason Priestley & Shannen Doherty
The cast of Beverly Hills, 90210 was an incestuous one. According to multiple members, everyone slept with everyone! But they were more flings than anything else. Jason (a.k.a. Brandon Walsh) said, "Nobody ever got attached. We never let it get in the way what we were doing."
Still, that doesn't take away the fact that he hooked up with his on-screen twin, Shannen (a.k.a. Brenda Walsh) — he said so himself!
Katherine Heigl & Jason Behr
It was October 1999 when future Grey's Anatomy star Katherine began her relationship with Jason — the same year their sci-fi series, Roswell, went on the air. The two played alien siblings Isabel & Max Evans.
They were dating a little over a year when they got engaged in 2001, but called off the engagement in August 2002 — the same year Roswell ended.
Jennifer Carpenter & Michael C. Hall
A year into filming Dexter, on-screen adoptive siblings Jennifer (Debra Morgan) & Michael (Dexter Morgan) were dating off-screen. And things went quickly from there.
The following year, on New Year's Eve 2008, the two got married. It wasn't before long, though, that they announced their separation. The two decided to part ways in December 2010, and were divorced the same month in 2011. However, they managed to remain professionals for the sake of their hit show, and continued to shoot opposite each other until 2013 when the series came to an end.
Jennifer & Michael both married other people this year.
Peter Krause & Lauren Graham
A month after the pilot episode of Parenthood aired, on-screen brother & sister Peter (Adam Braverman) & Lauren (Sarah Braverman) kicked off their coupledom.
Even though the show came to an end last year, the pair's still going strong!
Barry Williams & Maureen McCormick
You'll never think of The Brady Bunch the same way ever again.
In her memoir, Here's the Story: Surviving Marcia Brady and Finding My True Voice, Maureen, who portrayed the eldest daughter, Marcia, on the series, spoke candidly about hooking up with her on-screen step-brother, Barry, who portrayed the eldest son, Greg.
While shooting some episodes in Hawaii, she said, they "couldn't hold back any longer. It was our first kiss, and it was long, passionate and deep. It was wonderful, too, though as we continued to kiss and press against each other so closely that we could feel each other's body heat." Though, it wasn't all hot. She explained, "A part of me — a tiny part, admittedly — said to myself, 'Oh my God! I'm kissing my brother. What am I doing?'"