On the latest "Grey's Anatomy," the Kepner sisters visited Seattle to attend April's bridal shower, which prompted April to make a big change to her wedding party.

In the episode, the Kepner girls arrive, and are practically unbearable. April (Sarah Drew) gets so fed up that she decides to fire her sisters as her bridesmaids and replaces them with Meredith (Ellen Pompeo), Cristina (Sandra Oh) and Arizona (Jessica Capshaw).

Meanwhile, Jackson (Jesse Williams) criticizes the emergency tracheotomy that Matthew (Justin Bruening) performs on a man whose tie got caught in a taxi door. Nevertheless, the situation somehow results in Matthew insisting that Jackson attend their wedding.

Cristina, who is hooking up with Shane (Gaius Charles), implants her 3-D print in an infant patient, but it doesn't work. Meredith then impants her 3-D print in a sheep, and it does work. Shane rudely congratulates Meredith on beating him and Cristina, prompting another fight between Meredith and Cristina. However, later, Cristina and Shane learn that their operation is going to work, while Meredith and Stephanie's (Jerrika Hinton) fails.

Arizona and Callie (Sara Ramirez) are still bickering, and realize that they may bicker less if they talk less. Also, Miranda (Chandra Wilson) takes the OCD medication that was recommended to her.

Jimmy (James Remar) shows up again at Grey Sloan, telling Jo (Camilla Luddington) that he's been trying to get clean after realizing that Alex (Justin Chambers) is his son. He then collapses, prompting Jo to take him on as a patient. Alex is angry at this turn of events, and Jo is endangered when Jimmy's hallucinations make him violent.

The next episode, "Get Up, Stand Up," will be the series' winter finale.

The synopsis reads: "On the day of April's wedding, the Grey Sloan Memorial doctors are all preoccupied with their own drama. Meredith and Cristina continue to argue about their research and careers, Bailey comes clean to Ben about her feelings regarding him moving back to Seattle, and Shane puts himself in a risky situation. Meanwhile, Derek gets a phone call that will change his life, on the winter finale of 'Grey's Anatomy.'"

Watch the promo below for "Get Up, Stand Up," which airs Thursday, Dec. 12 at 9 p.m. EST on ABC.