"This year, we might all go as circus members because the baby really, really looks like a weightlifter," she tells PEOPLE

By peoplestaff225
Updated September 29, 2015 01:00 PM

Ladies and gentlemen, boys and girls, Kristen Bell (and her brood!) might be joining the circus.

With Halloween fast approaching, the actress has already started thinking about themed costumes for her family of four — and one look at her younger daughter, 9-month-old Delta, and Bell’s imagination went wild.

“This year, we might all go as circus members because the baby really, really looks like a weightlifter and we want to give her little barbells,” she told PEOPLE at The Alliance of Moms Raising Baby Workshops For Pregnant and Parenting Foster Youth on Saturday in Los Angeles.

“I like everybody being something as a part of a group. Last year, the two dogs and the baby were dragons and we were Khaleesi and Drogo from Game Of Thrones.”

Stefanie Keenan/Getty

Bell, 35, and husband Dax Shepard, 40, are also parents to 2½-year-old daughter Lincoln. While it may seem like Bell has it all together, she admits, “I don’t really know how to do it perfectly. I’m trudging along like everyone else trying to do the best I can.”

When it comes to supporting other women, Bell wants to impress upon them that their experiences are common.

“I know when I was — especially a first-time mom — it can feel at moments … as wonderful as it is, so isolating and all you want to know is that other people are going through it as well and you’re not alone,” she explains.

As for her own two bundles of joy, Bell shares that Lincoln is “wonderful and gentle, thankfully,” as a big sister to Delta.

Stefanie Keenan/Getty

The House of Lies actress was on hand to support Alliance of Moms, a volunteer corps of mothers who support The Alliance for Children‘s rights.

“There are 28,000 kids in foster care in Los Angeles county alone. That’s more than any city in the United States,” Bell says.

“The Alliance of Moms exists to give those kids a support system to help them grow up.”

She adds, “I had been looking for a group that had infrastructure like this, where I could be of service to other moms who might feel isolated or like they’re lacking a support system.”

— Abby Stern