Being three years older, Randy had left home, gone to Indiana University and by the summer of 1968 was living and working in New York, where he'd played trumpet with jazz-rock pioneers Blood Sweat & Tears, pianist Horace Silver's quintet and Duke Pearson's big band, among other notable musicians.
Michael had followed him to Indiana and at the time had a student band with trumpeter Randy Sandke that played jazz-rock and had managed to get banned by Notre Dame Jazz Festival, the oldest collegiate jazz event in the US, for playing the Doors' Light My Fire.
"They must have been the best group ever to be banned by that august event," says Randy with a laugh. "I hadn't actually heard them at that point and I hadn't been getting home to Philadelphia much due to work commitments. So I hadn't heard Mike playing for about two years."
A stopover in Chicago just after the Notre Dame debacle allowed Randy to organise a jam session with Michael's band and some of the musicians Randy was on tour with at the time, including drummer Billy Cobham and saxophonist Bennie Maupin, both of whom would go on to make major impressions in the 1970s, Cobham with the Mahavishnu Orchestra and Maupin with Herbie Hancock's band.
"We got together and played and I'll never forget the look on Billy and Bennie's faces – all of our jaws dropped, including mine – when they heard Mike," says Brecker senior. "Since I'd last heard him he'd switched from alto to tenor and he'd obviously absorbed John Coltrane and Junior Walker and a whole lot of other influences. But although he was just 19 that summer and still developing, he was Michael Brecker as the world would come to know him even then, a really strong player with a great sound and fantastic stamina as an improviser. It was a real watershed moment."
The Breckers had grown up to the sound of jazz. Their father, Bob, a lawyer, played piano and when he wasn't entertaining musicians at home or out listening to jazz in the Philadelphia clubs, he would play records, especially those by trumpeters including Dizzy Gillespie, Miles Davis, Chet Baker and his particular favourite, Clifford Brown.
Randy can remember his dad coming home after hearing Brown in the flesh one night, grabbing Randy's arm and telling him, "Trumpet is the greatest instrument in jazz." This didn't stop Randy deciding that he wanted to play trombone, although his school's limited supply of musical instruments would soon put paid to that notion.
"They only had trumpets and clarinets, so at the age of eight I chose trumpet because it was closer to the trombone and when it came to Mike's turn he had clarinet foisted upon him, but that worked out okay later."
As the brothers became proficient on their instruments they'd play free improvisation together, usually in the bathroom where the acoustics suited them. They also played in the family band when dad came home from work, with Bob playing piano and vibes, their sister playing bass and Randy and Michael taking turns on drums.
As Glasgow Jazz Festival regulars may remember, Michael kept up his drumming chops and gave a fine display with his own band at the Old Fruitmarket a few years ago while his drummer, Ralph Peterson, switched to trumpet.
In his teens, although jazz remained his first interest, Randy played with many of the rhythm 'n' blues bands that were then proliferating in Philadelphia. So by the time he arrived in New York he was a seasoned player open to different styles of music. This served him well when he, along with Michael, became a prolific session musician, playing on innumerable records by an array of artists including Stevie Wonder, Frank Zappa, Yoko Ono and Charles Mingus. His first recording under his own name, Score, was made for a subsidiary of Blue Note Records no less in 1968, an auspicious occasion for which he flew his brother to New York so that he could take part also.
It was the beginning of a long professional partnership. They featured together in jazz-rock adventurers Dreams, alongside Cobham and guitarist John Abercrombie, formed a formidable frontline when Randy returned to Horace Silver's band and most famously, after Randy starred in guitarist Larry Coryell's Eleventh House, they formed the Brecker Brothers in 1974.
Well equipped to meet audiences' enthusiasm for dancing while appealing equally to those who preferred just to listen, the Brecker Brothers were the consummate blend of musical sophistication, gobsmacking instrumental virtuosity and deeply groovy fun. Like their friends the Average White Band, whose records the brothers also appeared on, the Breckers were fond of funky chants as heard on club favourites such as Sneaking Up Behind You and East River, the latter of which made the UK pop charts.
"We always had great rhythm sections, so the groove was always well taken care of and everyone had a good time," says Randy. "But at the same time, we didn't want to water down the jazz element too much. The jazz tradition, for me, was still strongly represented in our music."
Over two periods, from 1974-1982 and from 1992-2004, the Brecker Brothers achieved conspicuous success across the world, winning two Grammy awards at home and becoming the first contemporary jazz group to tour China. Separately they scored notable successes, too, with Randy adding to his Grammy haul (he's won five so far) with his 1995 celebration of Brazilian music, Into the Sun, and maintaining a consistently high standard in his solo recording career, and Michael producing a series of enthusiastically received albums for the Impulse! label as well as establishing himself as the most influential saxophonist of the past 30 years, although he was never very comfortable with that description.
In 2004, Michael was diagnosed with a rare form of leukaemia and although he managed to keep working, completing his final album, Pilgrimage, shortly before his death in January 2007, the brothers' appearance on the WDR Big Band in Cologne's celebration of Randy's compositions in 2004 was to be their last time onstage together.
Randy's concerts with the Scottish National Jazz Orchestra, paying tribute to Michael this weekend will repay the compliment to some extent but his brother is never far away from his thoughts.
"I listen to his music a lot just to remind myself of how great he was," he says. "As a saxophonist he was amazing but what's making me look forward to playing these concerts especially is that Mike became such a great composer. He started writing later in life than I did but he really concentrated hard on composing and arranging and I think you can hear that concentration, the hours he put into his music, shining through in the quality of his work."
Randy Brecker and the Scottish National Jazz Orchestra play the music of Michael Brecker at Greyfriars Kirk, Lanark on Thursday [May 24]; Queen's Hall, Edinburgh on Friday; the Royal Conservatoire of Scotland, Glasgow on Saturday; and the Adam Smith Theatre, Kirkcaldy on Sunday.