For fans, will the Jackson 4 add up?

When Jackie, Tito, Jermaine and Marlon bring their “Unity Tour” to the Greek Theatre on Sunday, they will perform hits from the Jackson 5 catalog. They may even bust a few vintage dance moves. But each knows it’s going to take a lot more than a rousing version of “Rockin’ Robin” to mask the bigger question surrounding the tour: Are they a viable act without Michael?

After the 27-date trek was announced in April, 11 stops were canceled, including shows in Cincinnati,Washington, D.C., and Dallas. Tickets for some performances, including L.A., have gone for as much as 66% off on discount sites such as Goldstar. The Greek Theatre, which seats 5,900, is still not sold out. The trek wraps up July 29 in Snoqualmie, Wash.

Jermaine says the slashed dates are not a result of low demand but, rather, a conscious decision to cut tour time in order to record the follow-up to their last album together, 1989’s “2300 Jackson Street.” “The whole thing was about doing small, up-close and personal venues. When we first started, we wanted to do a few dates,” Jermaine said. “[The tour organizers] threw a whole bunch at us.”

FOR THE RECORD:
The Jacksons: A July 21 Calendar section article about the Jackson family tour reported that several of Michael Jackson’s siblings had accused the executors of his estate of fraud, forgery and abuse of their mother, Katherine Jackson, but neglected to include a response. In a statement, the executors said the accusations were false and were “being made by certain members of Michael’s family whom he chose to leave out of his will.” —

The last time the Jacksons performed as a group in Los Angeles, they were closing out six dates at Dodger Stadium during their massive 1984 “Victory Tour.” On the final night, the group’s most famous member announced the tour would be their last.

The brothers disbanded after that, with only one moonwalking his way to superstardom and scandal. The last effort to keep the Jackson group franchise alive, “2300 Jackson Street,” featured just one track with the most famous of the bunch and failed to match or even come close to the group’s earlier triumphs.

Three years after Michael’s death and nearly 30 years after that December night at Dodger Stadium, the brothers — all between ages 55 and 61 — are hoping their “Unity Tour” can recapture some of the Jacksons’ former allure.

“My brothers and I, we’ve been doing this for so long, we’ve never been out of the business mentally,” Tito said from his home in Calabasas. “I had no concerns about the vocal work. We sang with Michael for many years and performed next to him all the way up to adulthood. Who better to sing [his] hits than his brothers?”

The brothers’ hope for a comeback was the focal point of their 2009 A&E; reality series, “The Jacksons: A Family Dynasty,” which premiered six months after Jackson died in 2009 after receiving the anesthetic propofol for insomnia.

Initially filmed as a one-off, hourlong special without Michael, the series was conceived to document a new album and tour in celebration of their 40 years in showbiz. The show was recast after his death and lambasted in the press as self-serving.

The brothers want to make it clear the tour isn’t the latest in a string of arguably exploitive projects cashing in on the late pop star’s legacy. Since Jackson’s death, there have been a video game, a Cirque du Soleil spectacle and a tribute show in Wales. Jermaine, like brother Randy, didn’t support the tribute because it happened during the high-profile criminal trial surrounding Michael’s death. Earlier this week several of the Jackson siblings (including Tito and Janet) made news when they sent a scathing letter to the executors of Michael’s estate, accusing them of fraud, forgery and abuse of their mother, Katherine Jackson.

Reclaiming the family legacy is at least part of the intent behind the new tour. “We all felt the time was now,” Jermaine said. “Had we jumped out of the gate right after he passed, they would have tore us apart, and we had no intentions on doing that.”

Rumors of the King of Pop hitting the road with his brothers (they last performed at his 30th anniversary spectacle in 2001, and various combinations have reunited) popped up frequently over the years.

“We were supposed to go on tour with Michael, right after his O2 Arena shows [in 2009],” Jackie said from Las Vegas. “He was supposed to take three to four months off, and then we were gonna tour around the world. And that never happened.”

The brothers are optimistic about their chances to kick start their career again — an outlook that’s likely ingrained when you’ve been famous as long as this family has. Still, performing songs they once did with their brother has not been easy.

“Michael was always on my right. Always,” Jermaine said. “[In] rehearsals I cried so much. You can’t hold back the tears. I do ‘Gone Too Soon.’ Sometimes I make it through. Sometimes it’s too tough.”

The four want to record an album of new material by year’s end or early 2013, which Jackie hopes can yield the Jacksons their first Grammy. They also hope to release a live album and DVD and take the tour overseas.

Jermaine said the intent is to incorporate today’s sounds, “but in that same record we’re gonna give that swing that they’re used to hearing too.”

Although the tour has been warmly received by critics, most reviews have been nostalgic takes on the Jacksons’ two decades’ worth of funk, disco and pop hits. The New York Times’ Jon Pareles wrote that the show “treaded carefully between respect and exploitation,” but more than once the fact has been acknowledged that the show just isn’t the same without MJ.

“When you have someone like Michael in the band — he was so incredible,” Jermaine said. “We are [now] doing what we probably wouldn’t get a chance to because he was our front.”

“Being on stage is a healing process for us,” Tito said. “Michael’s spirit is with us to sing the beautiful songs that we made together. We are doing what we were meant to do.”

gerrick.kennedy@latimes.com