'1000-Lb Sisters' Star Amy Slaton Flubs Sister Tammy's New Last Name In Wedding Toast

The Slaton sisters may be no more, but their relationship is still as strong as ever.

In a sneak peek for the Tuesday, March 21, episode of 1000-Lb Sisters, Amy gives a heartfelt toast professing her love for her elder sister while attending her wedding to beau Caleb Willingham — except she can't quite remember Tammy's new last name.

"You've always been my big sister. We've always been Amy and Tammy, Amy and Tammy, the Slaton sisters," she gushes of her close relationship with the 36-year-old in the clip. "But now it's like, Amy Halterman and Tammy — what was your last name? I'm sorry."

"Willingham," Tammy reminds her, but Amy flubs the name yet again, mistakenly saying, "Wilmington."

"It's not us no more. We're not the Slaton sisters no more," she continues despite the minor slip-up. "It's just butter sweet [sic] to end that era."

As OK! previously reported, Tammy met Caleb while they were both inpatients at an Ohio rehabilitation facility for their respective weight concerns. The 39-year-old asked her to marry him after only one month of dating, and the two said "I Do" in an intimate ceremony a mere two weeks later, so they could share their special day with their rehab friends.

"I honestly thought [she was] joking," Amy admitted in a recent episode upon learning about Tammy's hasty engagement. "But then again she’s always loved hard and loved fast."

As for Tammy, getting married to Caleb was nothing short of a fairytale.

"When I saw Caleb at the altar, I was just picturing doves and butterflies all around like God had opened up the clouds and let the sunlight in," Tammy said in a previous sneak peek of the highly anticipated Season 4 episode. "It was magical."

"Our wedding day was perfect, there was so much love in the room," Tammy later spilled to an outlet last November. "I literally married my best friend."

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Parade obtained the sneak peek of Amy's wedding speech.