Richard Engel took to social media to announce on Thursday that his six-year-old son, Henry, had passed away.
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Along with a photograph of a smiling Henry, he shared a heartbreaking statement on Twitter that read: "Our beloved son Henry passed away.
Richard announced the heartbreaking news on Twitter
"He had the softest blue eyes, an easy smile and a contagious giggle. We always surrounded him with love and he returned it, and so much more. Mary and Richard."
He and wife Mary also are parents to Theodore, three, and were quickly inundated with support from their followers and loved ones.
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Henry had been diagnosed with Rett Syndrome in 2017, a rare genetic disorder that can lead to physical and cognitive impairments at a very young age. It can also lead to stunted growth.
He shared another update on the way Henry's own cells could be used in furthering along research on the condition, which has no cure as of yet.
The Today team sent their love
"Researchers are making amazing progress using Henry's cells to help cure RETT Syndrome so others don't have to endure this terrible disease," he shared, to the support of his fans.
Today Show and NBC News' foreign correspondent shared a positive update on his son's condition on Twitter back in May, with a video of his son sitting up.
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"Thank you for the messages of support! Today Henry was able to briefly support himself in a seated position during physio for the first time in a long time. Go Henry!" he wrote.
The Today social media page also released a statement in support of Richard and his family, sharing a photograph of the family of three alongside his tweet.
Henry had been making slow progress
"Sending all our love to NBC News' Richard Engel and his family. Henry was diagnosed with Rett syndrome, a genetic brain disorder that does not have a treatment or cure, as a toddler," it read, quickly also earning the support of fellow NBC stars Hoda Kotb and Jenna Bush Hager.
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