When it comes to co-parenting, Rachel Bilson knows it's most important to always put the child first.
The actress shares 6-year-old daughter Briar Rose with ex Hayden Christensen and explains to PEOPLE in an exclusive interview how they found the trick to successful co-parenting since their 2017 split.
"Communication is key and just being on the same page, so everything's about the kid," she says. "As long as you put the kid first, everything will be okay."
The O.C. alum, 39, had to come up with a solution for her young girl when she developed eczema and found that a dairy-free lifestyle was just the ticket with the help of Planet Oat.
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"We had to take my daughter off dairy for like five or six months and it cleared up," she says, revealing that Planet Oat's dairy-free products made it an easy transition for the entire family.
"[Hayden and I] were both totally on board," she says. "When we went off dairy, we both were fully supportive of each other and her, so it worked pretty seamlessly."
Bilson reveals that she tried "all the alternative ways and options" and that Briar couldn't tell the difference when using Planet Oat's oat milk to make things like pancakes and fudgsicles.
"We really substitute oat milk in a lot of things that we cook," she says. "My daughter loves overnight oats, so we do that all the time. We have it ready to go on busy mornings for school; it makes it super, super easy, and we also have fun with it."
The former Hart of Dixie performer points out that her mom is also vegan so they're a "very oat milk-forward house," and that being stuck at home during the pandemic forced Bilson and her daughter to get creative in the kitchen together.
"Isn't everyone a professional chef now after the last year?" she says with a laugh. "We did a lot of baking and experiments. My daughter loves to make up her own recipes, which you know how that goes — especially with baking — but we had fun with it."
Like all parents, Bilson had to spend the last year homeschooling her child, which meant having "to come up with all these different things" in the kitchen for recess and lunch so that Briar wasn't eating the same thing every day. But she says her daughter has learned to enjoy spending time in the kitchen with her mom.
"I think it was more important than anything else to just have fun and do those things together," she says, joking: "I'm going to make her do all the cooking. I'm like, 'Briar, I need my coffee!' "
Greg Fiore for Planet Oat
Briar did attend in-person school by the end of the academic year, and her mom says the last year made the transition into full-time school a lot easier. Her main concern was finding ways to keep her family from going stir crazy while still being safe.
"I try to do active things with her, like bike riding, which is super fun," she says. "Being outdoors was huge during quarantine, making sure we spent a lot of time out in the backyard, finding fun activities to do outside."
While the last year wasn't without its challenges, for Bilson, it was a rare opportunity to get a "special" amount of quality time as a family.
"They're normally at school all day and you don't get the time that we got this past year being together," she recalls. "I think we were really fortunate, especially during the hardcore lockdown, because [Briar] was able to have two different places to go and there was variety and I think that really helped her."
Rachel Bilson/instagram Rachel Bilson (L) and Melinda Clarke
RELATED VIDEO: Rachel Bilson Opens Up About Co-Parenting With Ex Hayden Christensen
The star also launched her own project while stuck at home: the O.C.-recapping podcast Welcome To The O.C. Bitches, alongside her former costar Melinda Clarke.
"To be able to talk about something and laugh and hopefully bring some entertainment to people, I just felt really fortunate to be able to work from home and do that," she says. "We're having so much fun doing it, so it was the best thing that could have happened."
In the program's first few months, the two hosts have already made headlines for their comments about former stars like Mischa Barton, but Bilson says she has no regrets so far about their unfiltered takes.
"We're just having fun and being honest and transparent, especially with the experience on the show, which was awesome," she says, recalling her time on the series. "I don't think I've gotten myself into too much trouble."