I really think the way the Grandma is acting is kind of strange. I know if my grandsons went missing and my daughter was acting weird, I wouldn't be defending her. Really, the grandparents were too quick in stating that their daughter was a great mom. This behavior doesn't just show up. I also heard in an interview with grandma that her daughter wanted some bonding time with her little girl since they lived with them and grandparents spent a lot of time with her.
My daughter lived with us for 3 years and believe me, she bonded and had time alone with her boys. Just because they lived with us, didn't mean I was going to do all the childcare.
This is just my opinion, but I think the grandparents are hiding the fact that their daughter has some sort of mental issue or personality disorder. This girl looks crazy...you can see it in her eyes.
"Dying is just nature's way of saying, hey, you're not alive anymore!"