Some children are born into situations that pretty heinous:

A man who played video games for hours each day has been convicted of killing his 17-month-old daughter when she pulled out his Xbox console.
Jurors rejected arguments that Tyrone Spellman had confessed to protect the child’s mother.
After a day of deliberation, they convicted Spellman of third-degree murder and child endangerment, for which he faces up to 47 years in prison.
[…]
A post-mortem examination showed that Alayiah had suffered a broken arm about two weeks before she died – an injury that city social workers did not see on two visits to the house in late August, when they found the toddler well.

Here’s the amazing part, they social workers knew something was up, they visited the house twice and yet they left her there. Social workers don’t visit families unless they have a suspicion that there is abuse.
(via)