'The Walking Dead' teased Daryl's romantic love interest episodes earlier in a small moment you likely missed

• Warning: There are spoilers ahead for season 10, episode 18 of "The Walking Dead."
• Lynn Collins debuted on the show as a love interest for Leah.
• Carol first hinted at Leah on season 10, episode six during a conversation with Daryl.

If you thought the introduction of Daryl's love interest Leah (Lynn Collins) on Sunday's "The Walking Dead" came out of nowhere, you may want to revisit an earlier episode of season 10 stat.

Apparently, the show subtly teased Leah on season 10, episode six.

Melissa McBride, who plays Carol on AMC's zombie apocalypse series, said as much on AMC's aftershow, "Talking Dead" on Sunday night.

When host Chris Hardwick asked McBride if she was surprised that Carol already knew a bit about Leah on Sunday's episode, McBride said she's known for quite some time about a relationship in Daryl's life.

"In the 'Bonds' episode, in season 10, Carol has a line that sort of became a thing," McBride explained, referencing a conversation that takes place between Carol and Daryl. "It was something like, 'You can't just keep her dog forever,' or something like that."

"Her dog," McBride added. "That's what Carol said. Her dog."

If you go back to season 10, episode six, you can catch this moment 14 minutes into the episode as Carol asks Daryl about Connie and his interest in her. Daryl suggests their relationship isn't like that.

Carol tells him there aren't many people left out there these days and then tells him, "Years pass, Daryl. You can't hide out with her dog forever, Daryl."

In that moment, we now know Carol is speaking about Leah.

You may have missed this tiny hint because the captions for the episode don't catch Carol as saying, "her dog." Instead, the captions (at least on Amazon Prime) read, "your dog." But if you listen, you can distinctly hear Carol say "her dog."

McBride said the line stood out to her, causing her to question its significance to "TWD" crew.

"When I asked about her dog, they told me a little bit about what would be coming for Daryl, that he had a past relationship with someone," McBride said. "To what extent? I wasn't really sure. I didn't know until this episode."

McBride has been keeping this secret for a long time and it seems Reedus may have been as well.

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