Bay and Daphne are about to discover the switch of a lifetime on the new Christmas special of Switched at Birth.

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On Sunday, TV Line posted a sneak peek where Bay happens to discover something pretty unexpected. She starts turning up the volume of the radio as a rock version of "Oh Holy Night" plays. A lamp flashes in the background as well, giving insight to the new life that Bay has.

Daphne then walks inside where the music is surprisingly bothering her considering that she can't hear. She turns it down and Bay exclaims that she's the one who can't hear anything.

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Bay is also confused on how Daphne knew where to find her, but it just so happens that they're both in the house that Daphne apparently grew up in. This is when they realize that they have each other's lives.

And what's even more shocking is that the girls' moms called their daughters with the opposite names. As of now, they both go by the names that they were supposed to have if they had been brought home to the biological parents when they were born.

Check out the scene here.

This gives plenty of curiosity on the kinds of adventures that Bay and Daphne are going to have as they discover what would've happened to them in this scenario. Plus, how long are they going to be like this?

The Switched at Birth Christmas special airs on Monday, December 8 at 9 p.m. ET on ABC Family.

Tags: Switched at Birth television ABC Family