Such burials eschew the embalming, expensive caskets and concrete vaults or metal grave liners standard in U.S. cemeteries, replacing them with simple materials that decompose along with the body. Mia was laid to rest in a bamboo casket with a cotton sheath, a burial her parents said was simple and elegant and surprised some of the attendees.

“A lot of people said, ‘Oh my gosh, I didn’t know this was even a thing,’” said her mother, Aubrey Zinn.