An infant who has become a literal poster child for the U.S. anti-vaccination movement died from suffocation while co-sleeping with her mother, according to a report by NBC News that cites the baby’s autopsy results. Evee Clobes, a 6-month-old girl whose image has been used to put a human face on the anti-vaxx movement on highway billboards and picketers’ posters, did receive vaccinations 36 hours before she died, but medical documents seen by NBC News state her cause of death as accidental asphyxiation. In Facebook posts, fundraising campaigns, and online forums, the baby’s mother, Catelin Clobes, has claimed vaccines caused her child’s death and circulated stories about other families who claim vaccines killed their children. NBC’s report also suggests that the anti-vaxx movement has relied on grieving parents like Catelin Clobes to push their belief that vaccinations cause autism and death. In a comment to NBC reporters, Clobes is said to have rejected the autopsy’s findings, writing “I safely co-slept with my daughter, that has nothing to do with her death,” she said via Facebook Messenger.