Surname Saturday: "B" for Best

Since I am not aware of any "B" surnames in my direct line,  I have decided to write a short post about Francis Elizabeth Moore Best, my great grandfather Willard Calvin Moore's sister.
Francis was born in March 1873 in Tuscola County, Michigan to Calvin and Mary (Armstrong) Moore. On February 7, 1891, she married John Albert Best and had Helen (1892), James (1893), William (1895), Ada (1897), Laura (1901), Alvah (1904), Claud (1906) and Celia (1909).
The last time I can find her is in the 1910 Federal Census in Logan, Ogemaw, Michigan, living with her large family. Shortly after that, a descendant of one of her older children tells me that Francis took her baby daughter Celia and left the family. Apparently, they never heard from her again. I find this very surprising considering Francis' own mother died when she was a very little girl, so she knew what it felt like to grow up without a mother. It seems a strange choice to inflict upon one's own children. It makes me wonder if "leaving" was not of her own accord and, possibly, something sinister befell her.
I have searched for clues to her whereabouts many times and have found nothing. I have scoured the 1920 Federal Census looking for anyone with the first name Francis or Elizabeth with an eleven year old daughter. Every one of the women I found could be accounted for in 1910 or before. Where could she have gone? Did she completely change both of their names? Why would she do that in a time when a person could "disappear" with relative ease?  If she was running away from something, then why didn't she go to my great grandfather, who was already estranged from the family, for help?  Why didn't she ever contact her other children, even later in life?
I fear there is more to this story and it isn't good.
I can't help but question what really happened to Francis and Celia. I hope Celia grew up and lived a full life. I hope she and her mother were together and well. However, finding no trace or hint of them makes me doubt it. Hopefully, someday, one of Celia's descendants will prove me wrong when they Google her name and find me.