"Saturday Night Live" writer Jimmy Fowlie announced a tragic development in the search for his missing sister ... saying that she's "no longer alive." Christina Lynn Downer had been missing for months ... and Jimmy's been posting pleas on social media asking for help finding her. But on Wednesday, he said the LAPD has told his family that the search for Christina is no longer a missing person's case ... but now a homicide investigation. "Summer House" star West Wilson 's cousin, Dakota Sweeney ,