Booth, 34, says she first started to notice a need for change when she went back to work after giving birth to Micah.
"I started to notice when I would go out for things for work, that there would be babies at castings all the time. And I was like, 'Why isn't anybody asking for my baby at these castings?' " she recalls. "Because they love [to cast] a real mom and real baby duo, it's easiest for everybody."
She says she had a productive conversation with her agents to send both Booth and Micah out for jobs, "whether they asked for kids with disabilities or not," Booth says, and thus she "began my journey of advocacy through representations of differently abled people in media."
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Booth says showcasing people with different abilities and features in media is important for and fully benefits everyone.
"The only reason I ever thought I could be a model is because someone that looked like me was doing it," she says. "So how do we more broadly advocate for our kids? 'Let's get them on TV. Let's put them in an advertisement,' so people with Down syndrome get to walk past store fronts and say, 'Oh, that person looks like me.' "
"Like either A, 'I want to be a model too' or B, 'I want to shop here because I feel invited to,' " she continues. "And then people who don't have Down syndrome and walk by a store, maybe that's their first time ever seeing someone with Down syndrome and it will get them to talk with their parents and say, 'Oh, this person looks different than me, what's going on here?' "
Booth, who now divides time between Los Angeles and Oregon, is a huge fan of open discourse and asking respectful questions.
"For so long, the disabilities community was shunned because people thought that's what you should do. 'Don't stare, don't whisper. Don't talk about this person with a limb difference. Don't talk about this person who wears their disability on their face, like Down syndrome,' " Booth says. "Now, as parents, we're like, 'No, let's talk about it. Hey, are you curious?' Like, 'Hey, kid at the park, come and ask me why my kiddo is stimming or doing these different things and I can tell you about autism and you can learn something.' "
She adds, "And then that 5-year-old is now going to live the rest of their life hopefully feeling comfortable around somebody with that type of disability, because they know a little bit about it."
Amanda Booth/Instagram Amanda Booth with husband Mike Quinones and son Micah
Booth says one of her many favorite things about Micah is his ability to sense kind-heartedness in others.
"Micah is this barometer that I get to have in my life," she says. "When he walks into a room, the most incredible experiences we ever have are the kids that are kindhearted that come over and engage with Micah. He brings that out of everybody in a way that is so authentic and just real."
She also appreciates how Micah teaches her to live in the moment and embrace unpredictability. "Having Micah has brought that back into my life and I think that that's a very important trait to have," she says. "I'm very thankful for that as well as the slowing down and presence. I mean, we can't skip ahead. I have no idea what tomorrow is going to look like or 10 years from now. No idea. And that's allowed us to feel everything."
She adds: "His soul is so pure, he's just a kind and loving person. His main job for himself is smiling, and he's clapping and he's giggling and that's his day. And for the rest of his life, as far as I can see from other people and their experiences, that gets to be his life. All the people I’ve met with Down syndrome are beautiful, present human beings. And that is just the wildest gift."
For more information about Down syndrome or to donate to research, education and advocacy efforts, visit globaldownsyndrome.org.
PEOPLE’s second annual Kindness Issue is dedicated to highlighting the ways, big and small, that kindness can make a difference and change lives. Click here and pick up the issue, on stands Friday, Oct. 30, for more stories on the impact of kindness from Priyanka Chopra Jonas, Sterling K. Brown, Heather Locklear and other stars, as well as everyday people practicing kindness in their communities. To share the story of someone who’s done something exceptionally kind, email firstname.lastname@example.org.