Chrissy Teigen and John Legend are now parents of four — sons Wren and Miles and daughters Esti and Luna

PHOTO: CHRISSY TEIGEN/INSTAGRAM

Chrissy Teigen is sharing a lesson she took away from a painful time in her life.

Speaking with PEOPLE about the launch of the Wonderfold W4 and W2 Petal Pop Stroller Wagon — a wagon specially designed by the Cravings cookbook author, 37, with a custom floral blooms print that carries four little ones, benefitting Baby2Baby — Teigen talks about how the colorful design was inspired by her heartbreaking struggle with postpartum depression after daughter Luna, now 7, was born.

“If you saw the Architectural Digest, John [Legend] and I both are really quite a neutral palette when it comes to us as a couple. So our Petal Pop with the wagon was really important to me. With Luna, I started out thinking, ‘Oh no, I’m never going to have bright-colored toys.’ I wanted everything to fit in the house and look so beautiful and peaceful.”

“Once we started growing and having more children, I realized the importance of color in their lives and the importance for them to wear color and how it makes them feel fun and special. The idea of seeing things in color was really important to me because, with my first pregnancy with Luna, I wasn’t seeing things in color necessarily,” referencing her time with postpartum depression.

“It wasn’t until I got over that hump and really started to appreciate color that it really changed my mood. So I wanted something bright and beautiful and fun for them. That’s why the wagon embodies all the things I think children need to see, and really all of us. Having color in your world is really important.”

John Legend and Chrissy Teigen with their four kids.CHRISSY TEIGEN/INSTAGRAM

For Teigen, the partnership is also a nice way to support an organization close to her heart.

“I have been a long-time supporter of Baby2Baby. I think when I first became a mother, I really started to have a deepened understanding of wanting to really use my platform to be able to uplift and provide a nurturing environment for children to be able to thrive from birth on. And what I love about Baby2Baby was that not only was that support given to the children but to the parents as well,” Teigen says. “And we have always tried to support by donating.”

Wonderfold Wagon designed by Chrissy Teigen.WONDERFOLD

The wagon holds four kids, another special feature for Teigen, who welcomed her fourth baby, son Wren in July. Now adjusting to life with a family of six — which also includes husband John Legend, 44, daughter Esti, 7 months, and son Miles, 4 — Teigen is doing her best to make sure everyone gets their own love and attention.

“For me, the hardest part is making sure the older ones feel loved and taken care of and just as special as the babies, even though you might have your hands on the babies a lot more,” Teigen says of the adjustment.

“There’s a lot of diaper changing and feeding and it seems like you’re coddling these two little babies and they’re not getting enough. I was speaking with my therapist and I was like, ‘I’m having a hard time because I want to make sure that Miles and Luna feel like we still love them.'”

She continues, “I think any parent of multiple kids can understand that you want to make sure they still feel loved.”

Chrissy Teigen and kids in family photo.CHRISSYTEIGEN/INSTAGRAM

When it came to using a surrogate to complete her family with Wren, Teigen says she’s “just really happy” it turned out the way it did.

“It felt very much like a village. It felt very much like the way people in my mother’s family raised their children when they were literally living in the villages of Thailand. It just feels like such good camaraderie around each other and warmth and love.”

“I was never one of those people who believe in hoarding all of this love for myself. I don’t get jealous when my children love on somebody else or hug them. To me, more love is more love and that’s what I’ve always wanted and it’s been really working out for us. We’re so lucky.”