YouTube star Mikayla Raines, known for running the wildlife rescue sanctuary Save a Fox, has died by suicide at age 29 after being subjected to an "online bullying campaign."

Mikayla Raines' husband, Ethan Raines, confirmed her death Monday in a video posted on Instagram in which he described her as a "superhero" who had helped rescue hundreds of captive-born foxes.

Mikayla Raines was 20 years old when she established her nonprofit organization, Save a Fox, in Minnesota in 2017. As part of her fundraising campaign, she started posting content about the rescued foxes in her care on social media, which ultimately saw her gain 2.4 million subscribers on YouTube and more than 500,000 followers on Instagram, The Independent reported.

"She couldn't bear what she was feeling any longer, and she ended her life," Ethan Raines said in the video, adding that her death is "the biggest loss" to him and their daughter, Freya.

"We have suffered a loss that is unimaginable," Ethan Raines captioned the video. "Mikayla was truly the most amazing and inspiring individual I have ever known, and not having her here makes everything feel empty. I feel broken."

Ethan Raines said he would continue his wife's dream, adding, "I hope to have your support going forward so that we can do good in her name."

Ethan Raines also spoke candidly about the personal struggles his wife battled, including depression, autism, and borderline personality disorder.

"As many of you know, she was on the autism spectrum, and while that made her life very difficult, it allowed her to hyperfocus on one thing, and that one thing was obviously animals," he said.

"She was so sensitive to everything, which is a double-edged sword because, on one hand, it allowed her endless empathy for those in her care. But it also means that she took everything negative to heart."

Ethan Raines shared that Mikayla and her animal rescue nonprofit had become targets of an "online bullying campaign" in recent years, reportedly led by people she knew, some of who were affiliated with "other animal sanctuaries." He explained that this "hurt her a lot," and although she initially "pushed through," the situation worsened in recent months as people "she considered her close friends" began to take part.

"[Mikayla] felt as if the entire world had turned against her," he said. "She couldn't bear what she was feeling any longer. And she ended her life. And it breaks my heart that someone who is selfless and devoted her life to animals could have so much negativity pointed at her."

Concluding his video, Ethan Raines urged anyone who is "lost and hopeless" to "reach out to someone."

If you or someone you know is considering suicide, please contact the National Suicide Prevention Lifeline at 1-800-273-TALK (8255), text "STRENGTH" to the Crisis Text Line at 741-741 or go to suicidepreventionlifeline.org.

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