Just opinion
I suspect the other older child (who accused her of child abuse and was subsequently removed and charges then filed against FM on her behalf) has talked about William and that day.
Its probably not evidence enough.
I also suspect Williams DNA in the boot of grandma's car after the FPs have stated he has never been in it. Found after a witness put FM out in that car which she didn't tell police at the time.
Also probably not enough.
I suspect the other older child (who accused her of child abuse and was subsequently removed and charges then filed against FM on her behalf) has talked about William and that day.
Its probably not evidence enough.
I also suspect Williams DNA in the boot of grandma's car after the FPs have stated he has never been in it. Found after a witness put FM out in that car which she didn't tell police at the time.
Also probably not enough.