The eight adult children of a man who had dementia are suing the assisted living community where he lived, and related entities, maintaining that lack of supervision at an outing led to his disappearance and death.

Lubin Phipps accompanied other residents of Woodmore House Assisted Living to an off-site picnic in September 2015, according to the lawsuit, a copy of which was obtained by McKnight’s Senior Living. At some point, however, Phipps was unsupervised and wandered away, the complaint contends. His caretakers undertook a search and notified authorities, but he was not found. Phipps’ body was discovered nearby 22 days later, and the cause of death was ruled to be hypothermia.

“Woodmore lost him — a human being, not a piece of luggage at an airport,” the family’s attorney, Salvatore J. Zambri, told McKnight’s Senior Living, adding that the lawsuit seeks “full justice” for Phipps and his offspring.

The children are seeking a jury trial and compensation for pain and suffering that they and their father experienced, as well as reimbursement for funeral expenses and payment for other economic and noneconomic damages.

In addition to Woodmore House, also named in the complaint are sister entities We Care Adult Services, a medical adult day care facility, and Quality Connection Transportation. McKnight’s Senior Living did not receive responses to requests for comments made to all of the businesses.