Problem Child Meaning

(idiomatic, by extension) Someone or something persistently difficult or vexing; a frequent source of trouble or annoyance.

Example: 1926, "General Topic: The Problem Child," The Age (Australia), 30 Mar. (retrieved 11 June 2009):
  Of recent times very much has been said regarding the problem child, but as Lady Stradbroke pointed out last week but little is being done to cope with the menace that child is to itself and to the community.
2006, Alan Fryer, "The Children of Woodlands,", 21 Oct. (retrieved 11 June 2009):
  Hill was a problem child who was sent to Woodlands because his parents couldn't handle him at home.
1959, "Payoff for Pioneers," Time, 26 Jan.:
  [A]n ambitious supersonic carrier fighter called the F3H Demon . . . proved too heavy for its Navy-specified Westinghouse engine (in itself a problem child), and turned into a $265 million fiasco.
2009, Theresa Vargas, "Superintendent Thinks Small in Plan to Revamp Middle Grades," Washington Post, 16 Apr. (retrieved 11 June 2009):
  Locally and across the nation, middle schools have generally been regarded as the problem child for school systems.