Narcissists With Children

Children suffer the most from exposure to Narcissism.

This statement is likely to trigger defensiveness, denial, or even rage in a person who has Narcissism, because it would cause "Narcissistic injury". Those who have Narcissism can't stand to be exposed for not being "perfect", and especially for not being superior to someone else. Raising, teaching, and influencing children is one of the big image-makers and judgment-markers in our modern society, and therefore can be VERY important to any Narcissist who is using that as a building block for their image and ego.
In other words, whether they're ACTUALLY neglectful or abusive or not is MUCH LESS IMPORTANT to them than being SEEN AS a person who is neglectful/abusive or not.
Their reaction to even the random suggestion that they could be doing something abusive or neglectful toward children would NOT BE "Oh maybe I should take a look at what I'm doing, maybe I should seek some information or advice". Their reaction is more likely to be "That's a bunch of crap! I'm GREAT with kids! I'm a WONDERFUL teacher/parent/coach/counselor/relative! ..." with zero reflection about it.

Defensiveness only, deflection only, humiliation only, anger/rage only.

No wondering about whether they're making mistakes, that they could be doing something better, that they could LEARN something that they don't already know about themselves and their own actions, NO WORRY or CARE about the well-being of the children they're influencing, except for, MAYBE, one of their "favorites".
(Narcissists ALWAYS have "favorite children" and "scapegoated children" when they're around kids, the way other people have favorite foods, and food they don't like).

It is COMMON for a Narcissistic stepparent to try to drive a wedge between a child and the parent.
It is also COMMON for a Narcissistic parent to try to drive a wedge between a child and the other parent's partner.

A Narcissistic parent or stepparent will often even try to drive a wedge between the child and ANY adult or child who the child is connected to in some way.
Especially whom the child responds favorably to, and especially if the adult is a positive influence on the child (and not also a Narcissist), and ESPECIALLY if the Narcissistic parent or stepparent ENVIES the person for any reason, or FEARS that the person will expose the N's agenda or behavior.

It is also COMMON for a Narcissistic stepparent (or parent) to REJECT a child, literally, even try to get the child out of their living space and family, because the child does not PLEASE THEM, because the child's behavior is "difficult", because the child is physically or mentally handicapped in some way, or because the child has been abused or traumatized.

("Stepparent" can also be applied to non-married partners.)

Narcissistic teachers, coaches, counselors, caregivers, relatives, and others who live and work around children will do this as well.
It's about envy, jealousy, control, image, aggression and dominance issues, and self-preservation.

A Narcissistic stepparent, or parent, (or other child-caregiver/worker) will jump to "Disciplining" a child to "remedy" any situation, BEFORE they'll do something else, like normal guidance, spending TIME with a child, doing activities with a child, talking and listening, finding more activities for a child to be involved in, etc.

They will try to "discipline" a child who is "acting out" or seems depressed, INSTEAD OF seeking counseling or changing what they're doing.

They will BLAME A CHILD for all of the child's moods and behaviors that don't please them.

They will BLAME A CHILD for all moods and behaviors EVEN WHEN THEY ARE FULLY AWARE that the child has been through TRAUMA and/or ABUSE.

When they can't "MAKE" a child behave in a way that PLEASES THEM, they will REJECT the child, and then either neglect, abuse (verbally, emotionally, or physically), abandon, slander, or ostracize the child. 

Narcissist adults will REJECT A CHILD who doesn't make them feel pleasant feelings.
They will REJECT A CHILD who is of a RACE or SEX they're biased against, even in their own family.
They will REJECT A CHILD whom they ENVY for any reason
(adults who have 'NPD' can envy anyone, even animals, even prisoners, even slaves, even victims of crime like rape and assault, even people who are seriously ill or injured).

Since people with Narcissism don't have the ability to empathize, or comprehend "cause and effect", or see others as "real" and "valid", they can't understand that children are not the same as adults, and that they are LEARNING "How To Be" in the world, and that they ALL need solid, fair, predictable, empathetic and nurturing guidance and mentoring from the adults around them, WITHOUT bias and prejudice.
It's just not something they can grasp intellectually or otherwise.

Narcissists seem to be fully aware of how painful and life-changing traumatic events can be when something happens to THEM, and how others "should be there for them" and "should be understanding". But when something happens to someone ELSE, even a child, they seem to have no ability to apply any of that in any REAL way to the other person. Worse, Narcissists can either be a direct perpetrator of trauma toward a child, or will ALLOW someone else to bully, abuse, or neglect a child who's supposed to be in their care.