Murder is homicide. Not all homicide is murder.
http://legal-dictionary.thefreedictionary.com/homicide
Homicide:
The killing of one human being by another human being.
Although the term homicide is sometimes used synonymously with murder, homicide is broader in scope than murder.
Murder is a form of criminal homicide; other forms of homicide might not constitute criminal acts.
These homicides are regarded as justified or excusable.
For example, individuals may, in a necessary act of Self-Defense, kill a person who threatens them with death or serious injury, or they may be commanded or authorized by law to kill a person who is a member of an enemy force or who has committed a serious crime.
Typically, the circumstances surrounding a killing determine whether it is criminal. The intent of the killer usually determines whether a criminal homicide is classified as murder or Manslaughter and at what degree.
(snip)
So we can agree she killed her child?
http://www.hollywoodreporter.com/news/casey-anthonys-hair-discussed-widely-208757
Casey's mother, Cindy, was overhead in the courtroom saying, “She looks so beautiful.”
Her father, George, replied, “Yeah, her hair looks longer.” Anthony wore her hair pulled back for every day of her trial, where she was accused of killing her 2-year-old daughter, Caylee.
The Orlando Sentinel noted that she appeared relaxed, and her attorneys Cheney Mason and Dorothy Clay Sims, were "smiling and stroking her hair before the hearing began."
” in a necessary act of Self-Defense”
Slutmom: Honestly, Caylee was coming at me with what I thought at the time to be a knife, but I discovered Zanny had given her a rubber dagger.