The Ensign Group Inc., through its home health Cornerstone Healthcare Inc. unit, is entering the Seattle market with its purchase of Voto Home Health, a Medicare-certified home health agency servicing King County, Wash., it says in a release. The agency will operate as Rainier Home Health. Cornerstone subsidiaries now operate 20 hospice operations, 18 home health operations, and three home care operations in nine western states, the company says.