Mom says daughter suffered from illnesses and needed wheelchair, feeding tube; Gypsy Blanchard on what happened the night mom was stabbed to death; Man says he feels ex-girlfriend used him to kill her mom.

An investigation is underway in California after 13 siblings ages 2 to 29 were allegedly held captive in a home. 20/20 reports on the latest details coast-to-coast with those closest to the story.