It kind of makes me wonder if this offender knew that the phone would be found if he left it turned on. It seems like if he/she were really trying to hide these things they would know to turn the phone off so they could not ping it to find it.
There are offenders who do these things on purpose to confuse LE or get media attention.
If that is the case then it would seem like this person is experienced and organized and a sociopath..
I recall in the very beginning of this case, the media in the local Bay Area stated the cell phone was turned off (this was before it was found).
Also, I do not believe a sweatshirt could have fit in the JC handbag. I read and hear tee-shirt and jersey reported. I recall that day being on the cool side, so it makes sense Sierra would be wearing a sweatshirt early in the morning.
Musing out loud: The crime lab should have completed its testing, or close to it. Seems to me LE is keeping the results close to the vest.
As much as Marlene talks in circles, she, father and BF would have been vetted first thing by LE, so I am sure this is her personality, although the poor woman has to be going through hell.
As far as running away, Sierra was too hooked into her friends and SM. I doubt a 15-year-old could be 100% confidential and not tell anyone of her plans. If she didn't have her Samsung smart phone with her, she would have no need for another cell phone because she hasn't attempted to call anyone that we know of, so the cell phone necessity has turned into a moot point.
Finally, there has never been mention of the house keys. I find it unnerving if the keys were missing -- I would not want to stay in that house. Probably the locks have been changed, but it's still creepy to be there.
All JMO from following the case and reading Web Sleuths. I have been praying for safe Sierra's return every day. I am thankful for everyone on this site.
Pinging her phone helped LE find her body ... no thanks to Verizon.