Tristan Thompson has heard enough from a woman who claims he fathered her 5-year-old son, and he's gone the legal route.
The NBA star has filed a libel lawsuit against Kimberly Alexander, while also adamantly denying that he's the father of her child.

TMZ obtained the lawsuit in which Tristan maintains that he took a paternity test in January and said it "definitively concluded that [he] is not the father." He's even agreed to take another paternity test, so long as the lab is reputable.
Last week, the woman claimed that Tristan was the father of her child and accused his ex, Khloe Kardashian, of fixing his failed paternity test.
Via their lawyer, Khloe and Tristan quickly sent Kimberly a cease-and-desist letter … which she then posted on social media.

"We demand that you immediately stop defaming them with malicious defamatory lies and specious fabrications," the letter said, referring to Tristan and Khloe. "It is obvious that the reason you are spreading these lies about my clients is because you want your 15 minutes of fame."
The Cleveland Cavaliers forward maintains this is nothing more than an attempted cash-grab, alleging that Kimberly has fallen on hard times financially and is looking for a quick payout.
Tristan, by the way, admits that he and Kimberly did hook up, but he claims that was long before he and Khloe met. He also says the timeline proves he's not the father, as he says the hookup occurred during his rookie season in 2011.
Coincidently, the paternity story came out as Khloe vehemently denied that she and Tristan are expecting their second child together.