Might be good for kiddos, keep them kidnappers/traffickers away from them. Then again they may dig into the kid's body trying to get them out once they are known to be present. If only they could be planted in a way that was both safe and impossible to get out without the services of a specialist and this was well known. They may also opt to abuse the children, and quickly kill and dispose of their bodies too. There are pets that have these and they help to track them when they are lost. Risks either way.