Adolf Hitler Campbell and his sisters, JoyceLynn Aryan Nation Campbell and Honszlynn Hinler Jeannie Campbell, were taken from their Holland Township, N.J., home on Friday by the state's Division of Youth and Family Services (DYFS), Sgt. John Harris of the Holland Township Police Department told FOXNews.com.
Their father, Heath Campbell, is expected in court Thursday in Flemington, N.J., in connection with the case.
Kate Bernyk, a spokeswoman for the DYFS, said confidentiality laws barred her from commenting on the case or even confirming that the Campbell children were involved.
"DYFS has their reasons and they normally don’t release any information, so we kind of have to go on faith with them," Harris said. Police were not told what the agency was investigating.
"I’ve dealt with the family for years and as far as the children are concerned, I have never had any reports of any abuse with the children," Harris said. "As far as I know, he’s always been very good with the children."
Speaking generally, Bernyk said the state's "decision to remove a child is based on the safety and well being of the child and the risk to that child, and that decision is made in conjunction with the courts and the county family court judge."
The Campbells made national news last month when a ShopRite supermarket refused to sell them a birthday cake with Adolf Hitler's name on it. The story generated a slew of angry Internet chatter.
Forensic psychologist N.G. Berrill said naming a boy Hitler could be considered child abuse.
"Part of it is the infantile nature of the parents’ behavior," Berrill said. "You can name your dog something weird, but they think they’re making some kind of bold statement with the children, not appreciating that the children will have separate lives and will be looked at in a negative light until they’re able to change their name. It is abuse."
Last year, a New Zealand court removed a 9-year-old girl from her parents in order to change her birth name: Talula Does The Hula From Hawaii. In that country, officials do not deem a name abusive unless it causes serious bullying.
Heath Campbell told the Easton-Express Times last year that he named his son after Adolf Hitler because he liked it and "no one else in the world would have that name."
A paper to be published in March in Social Sciences Journal by economists David E. Kalist and Daniel Y. Lee of Shippensburg University found that unpopular first names, when mixed with factors like a disadvantaged home life, can increase the tendency toward juvenile delinquency.
Lee told FOXNews.com that Adolf and Hitler were not names they looked at for the study.
"Hitler most likely would be an unpopular name in the sense that not many people name their children with a name [like Hitler], but we didn’t particularly look at particularly bad names like that," he said.