9-1-1: Lone Star: T.K. Gets News That Could Derail His Wedding to Carlos in This Exclusive Clip

Will T.K. Strand (Ronen Rubinstein) ever catch a break on 9-1-1: Lone Star? With his wedding to police officer Carlos Reyes (Rafael L. Silva) on the horizon, the paramedic is about to receive some news from his father, Owen (Rob Lowe), that could change the rest of their lives — or at least how they choose to live their final years.

In last week's episode of the Fox procedural drama, Owen's half-brother, Robert (played by Rob's real-life brother Chad Lowe), made his first real trip to Austin to meet T.K. and Carlos and make up for lost time with Owen, whom he met for the first time last season while their father was in hospice care. While showing pictures of his teenage daughters at dinner, Robert had a little bit of trouble remembering his second child's name. Later, Robert confided in Owen that he was recently diagnosed with Huntington's disease, a hereditary disorder that causes the progressive degeneration of nerve cells in the brain, and has already begun experiencing tremors and cognitive issues.

As it turns out, Robert drove himself from Southern California to Texas to spend time with the family he never knew he had and to warn Owen about their late father's Huntington's diagnosis. And in TV Guide's exclusive sneak peek at Tuesday's episode, Owen has to break the same news to T.K., adding that he will be taking time off work to drive Robert back to California (and, therefore, making Jim Parrack's Judd Ryder the interim captain of the 126).

T.K. understandably doesn't take the news very well, asking if he should postpone or call off his wedding to Carlos. "Dad, I can't marry Carlos knowing that I have a death sentence hanging over my head," he says.

"Son, we all have a death sentence hanging over our heads," Owen responds. With 48 hours left until their lives could change forever, how will the Strands react?

9-1-1: Lone Star airs Tuesdays at 8/7c on FOX. Episodes are available to stream the next day on Fox Now or Hulu.