|“||Oh please, ma'am. Call me... Lalavava!||„|
Olga "Lalavava" Astronomonov, also known as Lala Fafa, is the younger sister of Mandark and a one-time antagonist in Dexter's Laboratory. She is the second in line of the evil children of the hippy pacifists Oceanbird and Windbear - albeit she is the little-known one.
Like her brother Mandark, Lalavava was voiced by Eddie Deezen with a slightly high-pitched voice.
She is not quite as ditzy as Dee Dee, and Mandark fears her, in contrast to Dee Dee's attitude toward Dexter. This is very similar to how Gaz is depicted on Invader ZIM. Mandark shares some similarities with his younger sister (such as their hairstyles), and they are both the opposites and rivals of Dexter and Dee Dee. Lalavava and her brother, Mandark, look very similar, in contrast to Dexter and Dee Dee.
Unlike their brothers, however, Lalavava and Dee Dee end up becoming friends. At the end of the episode Dee Dee's Rival, Dee Dee and Lalavava go to the mall while agreeing that science is lame.