If your birthday party doesn't involve you getting into a bikini and posing next to an alligator, is it even worth throwing? Leandra's photo shoot for her model-theme bash goes awry when the nonhuman guest starts misbehaving on Sweet 15: Quinceañera's Tuesday, October 18, episode, as seen in Us Weekly's exclusive sneak peek.

The TLC unscripted series' preview clip shows Leandra, 14, taking off her coat to reveal a bikini that she's wearing for the shoot. However, the alligator that wedding planner Alexis managed to wrangle for the event is a bit bigger than the birthday girl was expecting.

"When Alexis told me I was taking pictures with a 9-foot alligator today, I was shocked," she tells the camera. "I'm really scared of this alligator, but I have to suck it up because this is what I wanted."

Alexis, who plans parties and owns a dress shop in Miami with cousin Jarling, reveals that he was a bit uneasy about how Leandra's dad might react to the skimpy outfit.

"I kind of looked at Dad to see if he's going to, you know, stab me in the neck or something," Alexis tells the camera.

Leandra ends up posing for a few pics while holding the reptile's leash, but handlers soon have to step in when the gator starts getting unruly.

"I was just like, 'OK, I might die today,'" Leandra quips. And Alexis tells the camera, "Everyone is panicking. Maybe this thing is not so safe."

This isn't the show's first bout with a feisty creature. The October 4 episode featured a baby tiger losing its cool while pics were snapped.

Watch the wild clip above. Sweet 15: Quinceañera airs on TLC Tuesdays at 10 p.m. ET. 

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