Facts: The Child had high-functioning autism and delayed speech. About five years after an agreed order, Mother began experiencing episodes of delusions and paranoia. Mother abruptly stopped taking her medications, and her episodes became more frequent. Mother was involuntarily hospitalized. The court appointed Father as the Child’s temporary sole managing conservator. After trial, the court made those designations permanent.

Holding: Affirmed.

Opinion: A parent’s deteriorating mental health can qualify as a material and substantial change that supports modification of conservatorship or limits on possession or access to the child. The evidence of Mother’s mental-health deterioration was not limited to the isolated hospitalization incident — Mother was not sleeping, eating, or taking her medications, believed people were watching her in her home, and believed people had inhabited the Child’s body.