Question: Frankie Valli was in what band with former Royal Teens keyboard and tenor vocalist?

Context paragraphs:
John Lloyd Young: John Lloyd Mills Young (born July 4, 1975) is an American actor and singer.  In 2006, he won the Tony Award for Best Leading Actor in a Musical for his role as Frankie Valli in Broadway's "Jersey Boys".  He is the only American actor to date to have received a Lead Actor in a Musical Tony, Drama Desk, Outer Critics Circle and Theatre World Award for a Broadway debut.  Young sang lead vocals on the Grammy-award winning "Jersey Boys" cast album, certified Platinum by the Recording Industry Association of America.  Young reprised his role as Frankie Valli in Warner Brothers' film adaptation of "Jersey Boys", directed by Clint Eastwood and released June 20, 2014.

Valli (album): Valli was the sixth solo LP album by Frankie Valli of The Four Seasons, released by Private Stock under catalog number PS-2017 as a stereo recording in 1976.  It was reissued on compact disc in 2008, paired with his first solo effort from Private Stock, "Close Up", by Collector's Choice.

Bill Kenny (singer): William Francis Kenny Jr. (June 12, 1914 – March 23, 1978), known professionally as Bill Kenny, was a pioneering African American tenor vocalist with a wide vocal range spanning four octaves.  Often regarded as one of the most influential high-tenor singers of all time, Kenny was noted for his "bell-like" vocal clarity and impeccable diction.  Although he is most famous for his role as lead tenor with the Ink Spots, Kenny also led a successful solo career after disbanding the Ink Spots in 1954.  Throughout the 1950s and 60s Kenny recorded, toured the world and appeared on many popular variety television shows.  In 1966 Kenny became the star and host of his own musical variety show "The Bill Kenny Show" which aired on CBC.  In 1989, 11 years after his death, Bill Kenny was inducted into the Rock and Roll Hall of Fame.  Kenny is often noted as being the "godfather" of R&B tenor vocalists.

Can't Take My Eyes Off You: "Can't Take My Eyes Off You" is a 1967 single credited to Frankie Valli.  The song was among his biggest hits, earning a gold record and reaching No. 2 on the "Billboard" Hot 100 for a week, stuck behind "Windy" by The Association.  It was co-written by Bob Gaudio, a bandmate of Valli's in The Four Seasons.  It was Valli's biggest solo hit until he hit #1 in 1974 with "My Eyes Adored You".

The Four Seasons (band): The Four Seasons is an American rock and pop band that became internationally successful in the 1960s and 1970s.  The Vocal Group Hall of Fame has stated that the group was the most popular rock band before the Beatles.  Since 1970, they have also been known at times as Frankie Valli and the Four Seasons.  In 1960, the group known as the Four Lovers evolved into the Four Seasons, with Frankie Valli as the lead singer, Bob Gaudio (formerly of the Royal Teens) on keyboards and tenor vocals, Tommy DeVito on lead guitar and baritone vocals, and Nick Massi on electric bass and bass vocals.

Jersey Boys: Original Broadway Cast Recording: Jersey Boys: Original Broadway Cast Recording is the Grammy-winning cast album for the Broadway musical "Jersey Boys", the story of Frankie Valli and The Four Seasons.  The album was produced by original Four Season, Bob Gaudio.  Principal vocals include Christian Hoff as "Tommy DeVito," Daniel Reichard as "Bob Gaudio," J. Robert Spencer as "Nick Massi" and John Lloyd Young as lead-singer "Frankie Valli."  It was released November 1, 2005 by Rhino Entertainment and reached number eighty-five on the "Billboard" 200.  In February 2008, the album was certified Gold by the RIAA.  As of December 2014, the album has sold 1.4 million copies in the US.

The Wonder Who?: The Wonder Who?  was a "nom de disque" of The Four Seasons for four single records released from 1965 to 1967.  It was one of a handful of "names" used by the group at that time, including Frankie Valli (as a "solo" artist even though the Four Seasons were present on the record) and The Valli Boys.  Wonder Who?  recordings generally feature the falsetto singing by Valli, but with a softer falsetto than on "typical" Four Seasons recordings.

The Proud One: "The Proud One" is a 1966 single written by Bob Gaudio and Bob Crewe and originally performed by Frankie Valli and The Four Seasons, and credited to Valli solo; that version peaked at #68.

Frankie Valli: Frankie Valli (born Francesco Stephen Castelluccio; May 3, 1934) is an American singer, known as the frontman of The Four Seasons beginning in 1960.  He is known for his unusually powerful head voice.

My Eyes Adored You: "My Eyes Adored You" is a 1974 song written by Bob Crewe and Kenny Nolan.  It was originally recorded by The Four Seasons in early 1974.  After the Motown label balked at the idea of releasing it, the recording was sold to lead singer Frankie Valli for $4000.  After rejections by Capitol and Atlantic Records, Valli succeeded in getting the recording released on Private Stock Records, but the owner/founder of the label wanted only Valli's name on the label.  The single was released in the US in November 1974 and topped the "Billboard" Hot 100 in March 1975.  "My Eyes Adored You" also went to number 2 on the Easy Listening chart.  "Billboard" ranked it as the No. 5 song for 1975.

Supporting paragraphs: Frankie Valli The Four Seasons (band)
Answer: Four Seasons