A seventh sibling, Bob's fraternal twin brother Richard, was never part of the band during its heyday, although he occasionally appeared with them in later years.

As the boys' musical and vocal abilities developed they began performing at church school dances in Stark County, Ohio.

Barbara, who would become known to their fans affectionately as "Mini-Mom" due to her diminutive stature, joined the group just in time to record the band's first album, including the hit single "The Rain, The Park & Other Things" with Bill on lead vocals.

Bob Cowsill is quoted as follows on the band's early days: Although Bill and I performed at a very young age, and Bill, I, Barry and John did a lot of frat parties at Brown University and clubs in Newport ... the most memorable performance of what I would view as the precursor of what The Cowsills would be was at Kings Park in Newport (right at the foot of Halidon Hall) at some carnival.

Mercury dropped us, but Artie and Steve had written "The Rain, The Park and Other Things" and we went in and recorded that song at A&R studios in New York and took the whole package to MGM, who decided wouldn't it just be terrific if their mother performed with them and, voila, the rest, as they say, is history.

Shortly after arriving, they received a copy of the "Hair" soundtrack album in the mail from the famed writer-producer-actor Carl Reiner, who was putting together a special for television called "Wonderful World of Pizzazz".

Working with house engineer Angel Balestier, the track was arranged and produced by Bob and Bill, who made sure that each member of the group got to contribute an individual vocal part to the recording, both in lead and background vocals, ensuring that each of the group's members would feature on screen when they performed it for the TV special.

Bill had an acetate of the song cut at DCT Recorders which ended up being played for a DJ at WLS (AM) in Chicago where it generated significant attention.

[4] A stereo mix of this elaborate studio version of "Hair" subsequently became the opening track for "The Cowsills in Concert" album, which was released in May 1969.

Musically, it heavily featured Bill since he'd been present for the recording sessions, but aside from a couple of songwriting credits, his name does not appear on the album.

The individual members went on to various career attempts in and out of the music industry, but they did appear at Madison Jr. High School in Tampa, Florida as "The Cowsills" for one performance during the mid-1970s.

One project in particular was a band called Bridey Murphy,[12] which was formed in the mid-'70s and featured Paul, Bill, Barry, and Waddy Wachtel, and performed to varying degrees of success.

[13] In October 1978, they played a show at Blackie's Bar in Los Angeles which was favorably reviewed by Billboard in the weekly "Talent in Action" column.

[18][19] After working as a sound engineer for Helen Reddy, Paul Cowsill left music for a career in the construction industry.

In October 1989 Bob, Paul, John and Susan again regrouped as The Cowsills playing club dates in Los Angeles and appeared in concert for the syndicated radio show, "The Lost 45s with Barry Scott" on July 1, 1990.

[20] The original plan was to simply hit the "oldies circuit", but after some deliberation, they decided to showcase new material written by Bob and his wife, Mary Jo.

This incarnation of the band started playing small clubs and showcases in the Los Angeles area and eventually spread out to similar venues across the country and into Canada.

Most notable of these events were "A Taste of Rhode Island in 2000", which featured all seven surviving Cowsills, and "A Family Thing 2",[22] which was a benefit concert in 2004 for Bill's medical and financial difficulties at the time.

This concert took place at the El Rey Theatre in Los Angeles and included an appearance by Shirley Jones, who introduced the band.

In October 2004 Bob, Paul, Barry, Susan and Richard reunited to sing the national anthem at Fenway Park before Game 4 of the 2004 American League Championship Series between the Boston Red Sox and New York Yankees.

The album features harmonies from her surviving brothers (Bob, Paul and John) as well as appearances by Jackson Browne and Vicki Peterson, and was released May 18, 2010.

[26][27] As of 2024, the group consisting of Bob, Paul and Susan, and occasionally John, still perform and since 2015 have appeared on the annual "Happy Together" package tour with the Turtles and several other sixties era bands.

[citation needed] They starred in their own television special, called A Family Thing, in November 1968 on NBC, which guest-starred Buddy Ebsen.

[31] By 1969 Screen Gems approached the family to portray themselves in their own TV sitcom, but when they were told that their mother was to be replaced by actress Shirley Jones the deal fell through.

Screen Gems later hired Jones' stepson David Cassidy to join the TV show The Partridge Family, and to have a four-year run on ABC Television.

The film, directed by Louise Palanker and co-directed / edited by Bill Filipiak, tells the behind the scenes story of the family, their rise to fame and subsequent fall due to their father's controlling and abusive nature.

In 2019, Bob, Paul, and Susan Cowsill were interviewed by journalist Rod Labbe for RetroFan magazine, in which they discussed their careers and lives together and apart.