fall through the cracks

Related to fall through the cracks: give it a shot, cut some slack, run an errand, slip through the cracks, To Say the Least

fall through the cracks

To go unnoticed or undealt with; to be unintentionally neglected or ignored, especially in a corporate, political, or social system. Because so many other social issues take priority for the government, such as drug addiction and unemployment, the welfare of children in the foster system very often ends up falling through the cracks. We were all so busy drawing up the contracts for this new deal that the thank-you dinner we'd promised to our interns simply fell through the cracks.
See also: crack, fall, through
Farlex Dictionary of Idioms.

fall through the cracks

or

slip through the cracks

mainly AMERICAN
If people fall through the cracks or slip through the cracks, they are not helped by the system which is supposed to deal with them. I would like to see some system or program in place to catch high risk kids before they fall through the cracks. This family slipped through the cracks in the system and they are not eligible for aid. Note: The usual British expression is slip through the net.
See also: crack, fall, through
Collins COBUILD Idioms Dictionary, 3rd ed.

fall through the cracks

To pass unnoticed, neglected, or unchecked: "In the past, many learning disabled children fell through the cracks" (Judith Harkness Richardson).
See also: crack, fall, through
American Heritage® Dictionary of the English Language, Fifth Edition.
See also:
  • slip between the cracks
  • slip through the cracks
  • slip through the net
  • through the cracks
  • have a loose tongue
  • loose lip(s)
  • loose talk
  • leave good (enough) alone
  • by coincidence
  • coincidence