Chrissy Teigen and John Legend are opening up about their grief following their pregnancy loss in September.

Teigen shared a heartbreaking post on Sept. 30 of her second-trimester pregnancy loss at 20 weeks. She later shared an emotional essay in which she detailed the medical complications she suffered and reflected on the loss of their son, Jack.

During an appearance on "Good Morning America" on Tuesday, Teigen and Legend spoke about how they are coping and how they've garnered strength from others by sharing their story.

"I definitely give myself permission to feel complete and utter grief," Teigen said. "Every day is so different. So when people ask me how I'm doing I always say I'm okay -- today."

"I didn't know that we could experience this grief and also share it, but when we did it really meant so much to so many people," Legend said. "And it was such a powerful experience for me to learn that. I'm just grateful that my wife was courageous enough to do it."

Teigen said she's received "thousands of letters" from supporters during this time.

"Obviously it's so painful to go through something like this, as a woman -- something that was inside your body that you were nurturing and taking care of -- obviously there's a father involved," she shared. "The support for the both of us has just been so beautiful, so incredible."

"This has been a lonely time for so many people because we're all separated physically in so many ways, and just the outpouring of people's love and concern for us has truly been heartening and lifting for us," Legend said.

"The world is inherently good. I believe people are inherently good, and it's shown itself," Teigen added. "As hard as it was, it is beautiful to see this side of it."

She also spoke about her decision to share the deeply personal photos from the hospital after losing her son Jack.

"I don't care if you were offended or disgusted," Teigen said. "I understand it could be that way for people." She said the photos were "designed for the people that were hurting."

She also added that her husband was "very uncomfortable taking them."

"She felt like really, that one of the ways we would carry on Jack's memory was taking pictures of that moment," Legend said. "I was like worried, I was like, 'I don't want to like commemorate this pain.' But the crazy thing about having a miscarriage, is you don't walk away with anything you have this emptiness -- and we wanted to take the photos so that we had something to remember."

Through this experience, the couple's bond has strengthened, Legend said, describing their relationship as, "stronger together than we've ever been."

"I just know that I love my wife, more than ever," Legend said. "We've been through so many challenges together and they've made her stronger, and I know that doesn't always happen when people go through tragedy."

"But I feel like the challenges we face together have made us feel even more sure about who we are together as a couple, and who we are as a family," he added.

Legend says their 4-year-old Luna and 2-year-old Miles have helped them by bringing them "so much joy, every single day and so much adventure every day."

"You don't want to be stuck in bed when you hear the laughter downstairs," Teigen said. "It helps so much."

In order to help families and others who are suffering during this time, the couple are using their voices to show support for Ronald McDonald House Charities’ newest initiative, #HereForRMHC.

The nonprofit’s new social campaign involves users sharing a photo or video making the RMHC heart symbol and the including the hashtag, #HereForRMHC, to Instagram, Twitter, TikTok or Facebook.

McDonald’s has pledged to give $100 in each participant's name as part of their $100 million commitment over the next five years. Entries must be submitted before Dec. 31, 2020.

The couple want to help raise much-needed funds for the charity, as contributions have declined due to the pandemic. "You know you've seen this year, with COVID especially, that people need their families close to them when they're going through an illness, and a lot of families can't afford to be there," Legend said.

"As long as you care for children, there's nothing else that you do aside from be a part of this initiative," Teigen said. "Because this is bipartisan -- loving your children, wanting the best for your children and wanting to keep families together for us is insanely important to us."