Tristan Thompson is fed up with what he …

Tristan Thompson is fed up with what he calls out-and-out lies about him fathering a child… so he’s followed through with a lawsuit against his accuser. Tristan just filed the suit against Kimberly Alexander … the woman who’s very publicly claimed the NBA star is the father of her 5-year-old son — something he’s repeatedly denied. In the lawsuit, Tristan says the paternity test he took back in January “definitively concluded that [he] is not the father.”