Mother gets probation in son's jaywalking death

This is a case that sparked my interested and a discussion at work last month. About a month ago a Marietta mother was sentenced to one year probation and 40 hours of community service for the jaywalking death of her 4 year old son. I personally have never heard of a case like this before. Is it right for a mother to be charged with vehicular homicide for jaywalking? For those of you who are not familiar with the case here is a basic breakdown of the facts: The mother was attempting to cross a five-lane street to get to her apartment. The bus stop she was dropped at was three-tenths of a mile from a crosswalk. The mother and her children made it to the median when her daughter darted out and her son followed. From news reports thats when them mother yelled for them to stop and the truck struck. Her 4 year old son died.

Here are my questions/issues with the case:
1. The driver plead guilty to hit-and-run and was sentenced to six months. My issue is in the late 90s he was also sentenced to two years for two hit-and-run accidents!!! I believe they were also on the same street!  So the mother faced up to 3 years in prison and the driver was only sentenced to six months. I do not know all the evidence just what I have read in reports but this seems a little unjust.
2. Why is the Marta bus stop three-tenths of a mile form the nearest cross-walk anyway??? Seems there should be a case against Marta as well, right?

Now I do understand parents are responsible for the care of their children, but is it justified to sentence her to vehicular homicide for not crossing in a crosswalk? I was a little surprised that the state took action against her. Some people have questioned the use of taxpayers money in bringing this suit forward. Also, the possibility of another trial since the judge offered her a chance to have her recorded cleared with a new trial.

Would love to hear some opinions on this cases. The mother's name is Raquel Nelson if anyone is interested in further case details you can simply google her.