I do think there is a case for negligence on the parents behalf, and I certainly think that had it been a single parent or perhaps even working class, some very different reactions would have taken place with the different organisations involved and the people following their plight. Whether that is the responsibility of the media or some perverse class system within the soicety, I wouldn't like to guess.
However, I also think that the most horrendous punishment for neglecting a child, no matter how unintentional, has already happened to these parents and see no need to persecute them further, I don't imagine anything anyone says will be able to make them feel worse than they already do. As to whether they're guilty or not, when faced with a distinct lacks of facts, and having some confidence in the law of the land even if I don't always agree with it, I would go to the default innocent until proven guilty setting.