They split up in September after 10 years together.
But Rachel Bilson and Hayden Christensen re-united to take their three-year-old daughter Briar Rose trick-or-treating in Los Angeles on Halloween.
The O.C. star, 36, and her Star Wars ex, 36, were bundled up for the autumn weather as their adorable girl was dressed in a pumpkin costume.
Co-parenting: Rachel Bilson and Hayden Christensen, both 36, re-united to take their three-year-old daughter Briar Rose trick-or-treating in Los Angeles on Halloween
The co-parenting champs looked to be in good spirits as they held hands with their baby girl to collect goodies in the neighborhood.
At one point, Hayden picked Briar Rose up and gave her a ride on his shoulders as they crossed the street.
A source told US Weekly: 'She's full-time back in Los Angeles and he's in Toronto. They've been on the outs for a couple of months.'
Sparks flew when the acting duo met on the set of science fiction flick Jumper back in 2007. Their whirlwind romance saw the couple get engaged after a few months.
Bundled: The duo were bundled up for the autumn