Is Brian Griffin returning to “Family Guy”? Fans of the long-running Fox animated comedy have been speculating that the family dog will return from the dead in the upcoming Christmas episode … but the new opening credit sequence says otherwise.

“Family Guy” returned on Sunday, Dec. 8 with its first episode since Brian’s death in episode 6, “Life of Brian.” And while the Griffin’s introduced their new dog Vinny shortly after Brian’s demise, it was still a shock when viewers tuned in for the opening credits this past Sunday and saw that Vinny had replaced Brian in the sequence.

Fans are used to the opening credits which feature the whole Griffin family singing and dancing. The sketch used to have Brian next to Stewie, but in the Dec. 8 episode the show decided to remove Brian and instead feature Vinny.

But Vinny’s replacement in the credits has viewers suspicious. How was the dog able to learn such a complex song and dance number so quickly? Fans are now questioning Vinny’s alibi for the day of Brian’s accident and wondering if the dog plotted Brian’s death.

The conspiracy theory isn’t too far out there (besides the fact that we’re talking about a cartoon). As “Family Guy” executive producer Steve Callaghan explained to E! Online, Vinny is “a lot more rough around the edges.” The dog obviously lived in the Quahog, Rhode Island area and it’s possible that he saw what a sweet life Brian was living – drinking Martini’s, traveling through time and constantly dating beautiful women that didn’t care he was a dog. The theory is that Vinny’s jealousy lead him to off the Griffin’s family dog and weasel himself in as the replacement. (I mean, Vinny is voiced by former “Sopranos” star Tony Sirico.)

It’s unknown if Vinny has any real connection to Brian’s untimely death, but “Family Guy” fans have a feeling that the new dog won’t  be sticking around long. Another theory surrounding the series is that Brian will be returning in the Dec. 15 episode, “Christmas Guy.”

A leaked synopsis for episode 8 teases the following:

“When Carter Pewterschmidt cancels the annual Quahog Christmas carnival, because he hates the holiday, Peter must transform his father-in-law from a Scrooge into a hometown hero in order to salvage the event. Meanwhile, Stewie devises a master plan to get the one and only thing he wants for Christmas in the all-new "Christmas Guy" episode of FAMILY GUY airing Sunday, Dec. 15 (9:00-9:30 PM ET/PT) on FOX.”

The fan theory is that Stewie’s “master plan” in the holiday episode is to get Brian back. Do you think Brian will come back from the dead? Is Vinny innocent … or are you suspicious of the new dog? Let us know your thoughts in the comments section or send a tweet to @AmandaTVScoop.

For more “Family Guy” scoop and spoilers follow Amanda Remling on Twitter - @AmandaTVScoop.