I am a seventh generation Californian, family going back to the Yorba's. Ysabel Yorba was a great-great-great (I don't remember how many) grandmother. She married a Yankee sea captain. There was a land grant given to Ysabel, from Oxnard to Santa Maria, by a Spanish king. I believe they named the homestead Gualasco Ranch. My sister and I are doing some more research, as mom claims she never listened to all the details of the heritage from her mom. I also have a distant cousin doing a lot of work. She has lots of newspaper clippings. Anyway, mom says the history is also in the Bancroft History of California. Good luck, and if you find a useful website, please let me know.