Here is the shakedown on Shuggie Otis

Had a few things worked out differently, soul singer Shuggie Otis could have been a huge star.

Instead, he spent almost four decades as someone people asked “Whatever happened to … ?” about. Despite being unable to get a recording contact after the commercial failure of his 1974 album “Inspiration Information” — now considered a masterpiece — Otis never stopped making music.

Now, he’s back on the road, supporting a reissue of “Inspiration Information” and the new “Wings of Love,” a collection of songs he recorded between 1975 and 2000.

Here are four things to know about Otis:

Music was a family affair.
Otis’ father was R&B musician Johnny Otis, who Shuggie began performing with when he was just 11. Otis also played on Frank Zappa’s “Hot Rats” album while he was still a teenager. The two of them met when Zappa interviewed Otis’ father for Life magazine.

He never hit the charts, but his song did.
Otis’ song “Strawberry Letter 23” was a huge hit for The Brothers Johnson in 1977, reaching No. 1 on Billboard’s R&B chart and No. 5 on the Hot 100. Otis has said royalty checks from their version of the song helped keep him alive during some of the more difficult years.

He’s no sideman.
Otis was asked to join The Rolling Stones as a guitarist after Mick Taylor left the group in 1974. He turned them down, and Ron Wood got the job instead. Otis also turned down offers to play with David Bowie and Blood Sweat & Tears because he wanted to make his own music.

His music is a frequent source for samples.
Otis’ music has been sampled by numerous R&B and hip-hop artists, including Beyoncé on “Be With You” and “Gift from Virgo” and Outkast on “Ms. Jackson.”

Shuggie Otis is playing SummerStage at Rumsey Playfield in Central Park on Sunday at 3 p.m., enter at 69th St. and Fifth Avenue, cityparksfoundation.org, FREE.