Before he started bashing skulls with his barbed wire bat Lucille on The Walking Dead, Jeffrey Dean Morgan starred in another hit TV series, The CW's Supernatural, where he played John Winchester, the father of Sam (Jared Padalecki) and Dean Winchester (Jensen Ackles). Back in October, Jensen Ackles initiated a humorous crossover on Twitter, when he reached out to his TV dad Jeffrey Dean Morgan, revealing that they found the bat Lucille in their iconic Chevy Impala, which lead to Jeffrey Dean Morgan telling his TV son that he needs his weapon back. While it seemed to be just a fun social media exchange, this Walking Dead crossover of sorts actually made it into last night's episode, much to the delight of fans on social media.

The opening moments of last night's episode, Somewhere Between Heaven and Hell, featured the Winchester Brothers, both bloodied from their previous battles, with Dean carrying the iconic barbed wire bat Lucille, before glancing at it and saying, 'Man, Dad loved this thing," before setting it on a table. It was certainly a quick nod, but a slew of eagle-eyed fans took notice, tweeting up a storm about this crossover. Even the official Twitter account for the Walking Dead comics took notice, sending out a tweet this morning about the crossover.

For those hoping that Jeffrey Dean Morgan may come back as John Winchester, that may be quite difficult. The actor already confirmed that Negan will be returning in The Walking Dead Season 8, and since Supernatural films in Vancouver and The Walking Dead is on the other coast in Atlanta, it may be difficult for the actor to find time to return as John Winchester. Jeffrey Dean Morgan played John Winchester in 11 episodes through the first two seasons of Supernatural, before he was killed in the Season 2 finale, and he also returned to voice John in a Season 3 episode as well.

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Supernatural has never had issues with bringing back dead characters in the past, so it's possible that he could return. The producers have said several times that they would love to have Jeffrey Dean Morgan back, so it seems that it's all up to Jeffrey Dean Morgan to decide whether he wants to return to the show, or if he even has the time to do so. Since Negan is such a pivotal character in both the TV series and the comics, where he's still alive, his run on The Walking Dead could certainly be quite lengthy, since the series is showing no signs of slowing down after seven seasons.

Back in January, The CW renewed Supernatural for a 13th season, and it's clear that this series isn't showing any signs of fatigue either. Producer Robert Singer and stars Jared Padalecki and Jensen Ackles recently teased that the show may come to a close with its 300th episode, which would be the 13th episode of Season 14, if the show is renewed again, but it hasn't been confirmed if this endgame is officially in the works. If that is the case, though, it would be interesting to see if the show finds a way to bring Jeffrey Dean Morgan back for one final appearance as the Winchester Brothers' father, John Winchester. Take a look at a collection of tweets regarding The Walking Dead crossover in last night's episode of Supernatural.