One of the articles I read some time back said that the maternal grandmother said she had a feeling her daughter was involved when she heard Shannon was missing, so perhaps she isn't a bad person and might be a good candidate to take custody of Shannon. If CPS decides to do that, I hope they do a full investigation first. I personally prefer a child to be placed with a relative than foster care, if at all possible.
CPS will usually try to find a suitable relative to place children with before putting a child in fostercare for two reasons. First, it is less unsetting for a child to go to stay with someone they already know and love and second, there are not enough foster homes anyhow. The only time they do not is if there is not a suitable, safe relative or the relative will not agree to only let the children visit with the parents as court ordered.