Corey Simms gets into an argument with Leah Messer's mom on Thursday's new episode of Teen Mom 2.

Leah Messer On Her Decision To Enter Treatment: 'Automatically, I'm A Drug Addict'

While exchanging Simms and Messer's daughters, Ali and Aleeah, 5, Dawn Spears confronts Simms with her idea of having the girls visit their mother in treatment on Mother's Day. However, because Spears refuses to reveal where treatment actually is, Simms doesn't want them to go.

“I really don’t want my kids to be going somewhere [and] I don’t know where they’re going," Simms explained to Spears in a sneak peek shared on Facebook on Monday. "She made the decision to go so that’s kind of all on her...She left on her own free will, knowing she was leaving her children for a month.”

Corey Simms Shares Elaborate Message On Twitter Explaining His Allegations Against Leah Messer

Although Spears feels her grandchildren should be with their mother on Mother's Day, her failure to disclose where Messer's treatment is has led fans to take Simms' side. On Facebook, viewers shared comments including those below:

"Corey is awesome.....he is the Dad and has every right to know where the kids are going....I am proud of him standing up for his kids."

"He is doing exactly the right thing. Who in their right mind would allow their children to go visit their drug-addict mother in an undisclosed location with their enabler grandmother?!"

For more of Corey Simms and Leah Messer, tune into Teen Mom 2 season six on Thursday nights at 10 p.m. on MTV.