NBC News correspondent Richard Engel announces death of 6-year-old son, who had Rett syndrome

Richard Engel, NBC News' chief foreign correspondent, shared sad news Thursday that his 6-year-old son Henry has died. Engel and his wife had been open about the child's battle with a rare genetic condition.

"Our beloved son Henry passed away," Engel wrote 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."

Henry, who was born in September 2015, was just an infant when his parents first realized he was not reaching developmental milestones, according to a tribute for Henry on the Texas Children's Hospital website.