A popular phrase in Phoenix, Arizona referring to someone whining. La Llorona (pronounced "lah your-OWN-uh") is the "wailing woman" of Mexican folklore, crying for her children, so calling someone "la llorona" means they cry a lot. I have no idea where the "twinkle twinkle little star" part came from though.
LaQueefah: Why am I single? I'm so fat! Nobody likes me!
LaFawnduh: Ohhh boo hoo la llorona la llorona twinkle twinkle little star! Fucking fug slut.