Ian Ziering, Luke Perry, Jason Priestley courtesy Everett Collection Ian Ziering, Luke Perry, Jason Priestley courtesy Everett Collection

Who's the daddy? That's the question 90210 fans have been asking ever since they learned that Kelly Taylor (Jennie Garth) has a 4-year-old son, Sammy.

Shockingly, the show's producers have announced that they'll reveal the identity of Sammy's father on Tuesday's episode (Sept. 16, 8 pm/ET, CW). Why give it up so early? "It worked with the stories we wanted to tell," says executive producer Gabe Sachs. "There are plenty of things we can still milk surrounding this story, believe me!" While he acknowledges that having said mystery daddy appear on the series is a "possibility," he claims he didn't contact the actor in question in advance of deciding to disclose his identity.

Everyone has their own theories, of course, most falling into one of two camps: Team Brandon or Team Dylan, echoing the series' push-pull love triangle that appeared to end in Dylan's favor when he and Kelly reconnected at Donna and David's wedding in 2000. Thus far, we've learned a few facts: Brandon apparently calls Kelly very late at night and tells Brenda to tell Kelly that "she's beautiful." We know that Sammy's father wants to be a part of Sammy's - and maybe Kelly's - life again. We also know it's a guy with whom she has a history that dates back to high school. Also, it sounds like Sammy's conception didn't take place as part of a stable relationship.

Who do you think it is? "It's totally Dylan, right?" I asked Sachs. "Look, it could be a lot of people, couldn't it?" he replied. Why yes, it could! Read on for my best guesses, and then leave yours in the comments section. - Mickey O'Connor

DYLAN McKAY (LUKE PERRY)
FOR HIM
Dylan has nostalgia working in his favor, as fans always found him to be a hotter match for Kelly than Brandon. If we are to believe the finale of Beverly Hills, 90210, they were back together as recently as 2000. Also, Dylan does have a reputation for taking off when things get complicated with the ladies.
AGAINST HIM Not a whole lot, frankly. Perry has said he wouldn't be interested in appearing on the new series, but come on, he returned to the old series, like, eight times. He'd totally do it.
LIKELIHOOD Very likely.

COLIN ROBBINS (JASON WILES)
FOR HIM
Kelly was totally into the sexy artist's program back in the day.
AGAINST HIM Um, he was kind of a really bad cokehead, you know?
LIKELIHOOD Very unlikely. While a Colin paternity would definitely up the drama, it would totally ruin Kelly's life, and she already has enough baggage from her mom's boozing and using for a lifetime's-worth of Al-Anon meetings.

STEVE SANDERS (IAN ZIERING)
FOR HIM
Talk about history: Steve and Kelly dated before the original series even started! Little Sammy has very familiar blond ringlets. Plus, Steve's famous actress mom is named Samantha.
AGAINST HIM Last we heard from Steve, he had shed his fratboy image, marrying Janet ( Lipstick Jungle's Lindsay Price) and having a daughter with her. Why would the producers break up his happy home?
LIKELIHOOD Slightly likely. Although Ziering has stated in the press that he won't return to the new show, it might be an elaborate smokescreen to keep us off the trail.

MATT DURNING (DANIEL COSGROVE)
FOR HIM
Matt was still in the picture at the series' end. He's an upstanding attorney.
AGAINST HIM Fans barely remember him. He didn't go to West Beverly, hence no high school past. Plus, Kelly dumped him, probably for being the lamest lawyer ever. Also: Matt who?
LIKELIHOOD Slim to none.

BRANDON WALSH (JASON PRIESTLEY)
FOR HIM
Thus far, the scripted hints have pointed to Brandon, particularly those late-night booty calls. Plus, despite what I said about Dylan above, the fans would also love a Kelly-Brandon matchup.
AGAINST HIM Brandon is a stand-up guy. If he knew he had fathered a child, he'd totally be coaching his T-ball team right now, not off in Belize doing God-knows-what until all hours of the morning. (Sorry, I think I was channeling Carol Potter there for a second.)
LIKELIHOOD Very likely. We know the producers are in touch with Priestley, who has said he would be willing to direct a few episodes. How easy would it be to cast himself as Sammy's daddy!

HARRY WILSON (ROB ESTES)
FOR HIM
Well, assuming Naomi's mom is telling the truth, we know his boys can swim!
AGAINST HIM Simple math. When Harry was 17, Kelly was 10, according to producers, which begs the question: What kind of history could they possibly have?
LIKELIHOOD Slim to none. Casting Harry as some kind of Sperminator would damage his credibility as a high school principal, don'tcha think?

DAVID SILVER (BRIAN AUSTIN GREEN)
FOR HIM
Shock value. Finding out that Kelly and David had, you know, done it would raise so many questions. Think of the narrative and dramatic possibilities!
AGAINST HIM A preview clip from Tuesday's episode shows a scene in which Kelly and Brenda reveal that Donna (Tori Spelling) has recently had a new baby, presumably with David, whom she married in the original series finale. There is also the fact that David's dad was once married to Kelly's mom, and they share a half-sister, Silver (Jessica Stroup). It's not technically incest, but it's pretty damn close.
LIKELIHOOD Don't rule it out just yet. I think it's the dark-horse possibility. Let's face it: If it's Brandon or Dylan, it will be boring, obvious and expected. I, for one, would look forward to those David-Kelly flashbacks; we'd all be asking with air quotes: How did that "happen"?

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