When it has become something else

The markers again, in one place.

You have hit your child in anger, or hard enough to leave a mark. You are frightened of what you might do. Your child is frightened of you, or has gone quiet and careful around you. Somebody else in the home is hurting the child. Your child has stopped eating or sleeping, is hurting themselves, or has said anything about not wanting to be alive. You are not managing the day and the child is going without. You feel nothing towards the child, and have not for a while.

That last one is on the list because it is very common after a birth, and after a bereavement, and in depression, and because people hide it hardest. It is a symptom rather than a fact about how much you love anybody.