Kennewick, WA- Results from the state crime lab could determine whether a Tri-Cities teenager accused of murder accepts a plea offer. 17-year-old Donald Schalchlin of West Richland is accused in the stabbing deaths of his mother and sister. Schalchlin's attorney and the prosecutor are still waiting for some evidence to return from the state crime lab. Sal mendoza says he wants to see those results before considering the prosecutor's offer. In court today, Prosecutor Andy Miller suggested if Schalchlin doesn't accept his offer, he could add additional charges, depending on what the crime lab tests reveal. Because of the slow process of DNA testing, the judge today pushed back the teenager's trial another month to April.