"After multiple assessments, after multiple evaluations, numerous medical professionals have felt that he needed a different fit in his medical needs, he needed more," Stauffer said.
In a comment posted to YouTube, Stauffer added: "Multiple scary things happened inside the home towards our other children."
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"I LOVE THIS BIG CRAZY FAMILY!!"
Stauffer features her family across her social media channels, which command hundreds of thousands of followers and regularly promote products from companies that pay Stauffer for the privilege.
She had one biological child from a previous relationship and one with husband James before the couple adopted Huxley from China in 2017. The couple would later go on to have another two children of their own.
She told followers last year: "I love this big crazy family!! Wouldn't change a thing about it."
Stauffer posted 27 videos about the adoption process, some sponsored, telling her followers that all the profits would go towards bringing Huxley to the US from China, Buzzfeed reported.
Writing for the website Parade last year, Stauffer said she was told by the adoption agency that Huxley had a "brain tumour" and "brain damage".
She outlined her initial hesitancy to a special needs adoption.
"But as we let the idea soak in, God softened our hearts," she wrote. "Before we knew it, we were open to almost every special needs in the book."
When Huxley came to the US, Stauffer discovered that his needs were more complex than she initially realised, having suffered a stroke in utero.
She regularly shared updates on their progress, detailing the challenges they had.
"And it started getting worse and worse," she told Moms.com in June 2019.
"And for me, it made me want to fight for him more. That's my personality. I'm a perfectionist.
"I'm a fighter. I am an advocate. If you tell me no, I'll say yes, and find a way to make it work."
"I FEEL LIKE A FAILURE"
After a barrage of questions from her followers, Stauffer and her husband eventually addressed the gaping hold in their family.
She posted a video to YouTube titled "An update on our family", detailing how they had "rehomed" Huxley.
The couple said that Huxley had been in "intense" therapy but felt that Huxley ultimately needed to be in another home for his emotional wellbeing.
"Do I feel like a failure as a mum? 500 per cent," said an emotional Stauffer, adding that they had never publically shared " "99 per cent of the struggles" they had with the boy.
After the couple discussed their decision, judgement came swiftly.
"My heart aches for poor Huxley," one person commented on Twitter.
"They dragged this poor little boy all the way from China, making him start all over again, then giving up on him."
"@MykaStauffer adopted an autistic child from China and after years of having him, she gave him up for adoption because he had 'bad behaviour' after using him for $$$ on her YouTube channel," wrote another.
One person raged: "She adopted a child for views and then got rid of him and treated him like a brand deal."
The hashtag #cancelstauffers was spawned, with many calling for Stauffer's sponsors to pull their advertising.
A change.org petition was launched, calling on YouTube to remove the monetised videos featuring Huxley.
"These people need to stop exploiting and profiting off of Huxley immediately!" the petition's creator wrote.
"The internet has your back Huxley. We hope you're happy and thriving wherever you are."
