If you
forget to check the locker and read Samantha's diary Latisha will not show. If you make it through the cleaning without checking out the diary and make it to your apartment, you will see the "thought cloud" that says, I should check her locker more. If you do check the locker more Latisha will come. The attached pic is from when I "forgot" to check the locker and followed the thought cloud . I went back to city view and to the gym and looked at the diary, then back to the apartment. Enjoy!