The Altadena Historical Society shares this tidbit -- yes, there WAS an Altadena dairy in Altadena, as well as a Highland Dairy on Highland.
All this and more is available at the Altadena Historical Society, which is open Monday and Tuesday from 9 AM-12 PM and Friday by appointment. This society is at the Altadena Community Center, 730 E. Altadena Dr., phone 626 797-8016.