Ok, let me see if I have the defense strategy:
Zanny was a co-worker of KC's at Universal although no Zanny ever worked at Universal, and was recommended by Jeff Hopkins to babysit Caylee because he used her to babysit his son, Zack, a good friend of Caylee's - although Jeff has no children. Zanny babysat Caylee for about 2 years so that KC could go to a job she didn't have and was paid $400 per week with money KC didn't have, although Zanny is rich and babysat out of love of Caylee. Zanny babysat Caylee at an apartment that she never inhabited during these 2 years but no one KC knows has ever met Zanny or heard of Zanny and Caylee did not recognize the name when it was spoken. KC does not have a phone number for Zanny, but Zanny has many phones with area codes all over Florida. Coincidentally, a Zanny viewed the same apartment a few days after the JBP incident, but it isn't the same Zanny.
KC dropped Caylee off at the stairwell of said apartment on June 9th between 9am and 1pm and hasn't seen Zanny or Caylee since, except for on June 16th at Jay Blanchard Park, where Zanny and her half-sister Samantha knocked KC to the ground, grabbed Caylee from her and took off in a car filled with Samantha's 3 children.
Zanny and Samantha threatened Caylee and the entire Anthony family and gave KC a script to follow or else. The script included stealing, lying, partying, shopping, smoking pot, watching movies, pole dancing and sleeping around with a few guys until a unspecified time when Caylee would be reunited with her loving, caring mother of the year.
Unbeknownst to KC, Zanny killed Caylee and entered the A home with her secret key to gather items that would frame KC for the murder. She then hid the body of the child in KC's trunk for a few days until she saw it parked at Amscot. She opened the trunk with her magic Nanny powers and saw that KC had not yet noticed the rotting corpse in her trunk, so Zanny stole the body back and drove it to KC's family neighborhood and dumped it in some flooded area behind KC's house which was also KC's childhood haunt.
Zanny has a magic umbrella which allows her to fly over rooftops and KC is 100% innocent.