Leonard Stogel's personal management firm, who introduced the group to M.G. M. An LP resulted which included "The Rain, the Park, and Other Things" (written by S. Duboff and Artie Kornfeld who also produced the disc). When released as a single in September 1967 this soon climbed the U.S.A. charts and reached No. 1 for one week with 16 weeks in the bestsellers, was a consistent seller for over three months and awarded a Gold Disc on 19 December by RIAA for the million sale. MGM sent them on a 22-city personal appeaance tour of the West Coast for one month, spending $250,000 on an unprecedented promotional campaign. Their concert at New York's Town Hall on 28 December was reported as one of the year's best pop concerts. Susan Cowsil (the eight years of age) was also presented and proved to be the cutest and sweetest eight-year-old in the business, and probably the most talented. 'Mom' Barbara also shone with her folk song number. The group's natural talent rocketed to the forefront particularly in the blues and rock items. The personnel of the group: Bill Cowsill (vocal), born 9 January 1948, also
writer of own lyrics; Bob Cowsill (vocals), born 26 August 1949; Barry Cowsill (vocals and bass guitarist), born 14 September 1954; John Cowsill (drums), born 2 March 1956; Susan Cowsill born 1959; Barbara Cowsill born 1928, who lends her voice to the quartet's close-harmony whenever it is needed.
The Cowsills were signed to an exclusive TV contract, with subsequent films and tours.