Rarely has an album title been less appropriate. There was nothing ‘Easy’ about the third, and final, LP of duets between Marvin Gaye and Tammi Terrell, released on September 16, 1969.

Throughout the recording sessions for the album, Terrell was in extremely poor health – the result of a cancerous brain tumor and the many surgeries she was undergoing as a result of her ailment. The young singer had suffered persistent headaches since her childhood, but it wasn’t until she collapsed on stage (into Gaye’s arms) at a show in October 1967 that doctors discovered her condition.

Following her first operation, Terrell was forced to retire from touring, but was able to record more material for Motown, including the second Gaye/Terrell album ‘You’re All I Need’ (with its accompanying hits ‘You’re All I Need to Get By’ and ‘Ain’t Nothing Like the Real Thing’) in 1968 as well as her first solo record, ‘Irresistible,’ in 1969. Sadly, the tumor continued to grow, forcing additional surgeries that limited Tammi’s ability to work in the studio.

When Motown founder Berry Gordy expected another Gaye/Terrell album for the fall of ’69, Marvin initially refused to take part. He had been growing more and more disillusioned with the business interests of Motown and Gordy (his brother-in-law at the time), and had become very protective of Terrell (the two had become close friends – platonically, by most accounts). Gaye was not interested in making music with his duet partner while she feeling so terrible.

However, Gordy convinced Gaye that the album sales would help Terrell and her family with the escalating medical bills. The singer begrudgingly set to work with the legendary writing/producing team of Nickolas Ashford and Valerie Simpson – who had worked previously with Gaye and Terrell. In two cases (‘More, More, More’ and ‘I Can’t Believe You Love Me’), Gaye was added to an already completed Terrell solo track. Otherwise, with Terrell laid up, the plan was that Gaye and Simpson would sing together on the initial versions of the tracks. Then, when Tammi was able to come to the studio, she could use Simpson’s vocal takes as a guide to record her own parts.

But there is significant controversy over if this actually happened on all of the album’s songs. In David Ritz’s biography of Gaye, ‘Divided Soul,’ Marvin was quoted that Terrell sang very little on ‘Easy’ due to her ill health and suggested that listeners were mostly hearing Simpson on the final version of the LP. Simpson disputed this claim, saying that she only sang the “guide vocals” for Tammi, who later sang her parts from a wheelchair. Let your ears be the judge: is that Simpson dueting with Gaye, or a less-than-100-percent Terrell?

Regardless, the album was released in September, containing a bunch of effervescent pop-soul that belied the strife behind the scenes. If ‘Easy’ didn’t match the artistic or commercial success of the duo’s previous albums, it still spawned four Top 50 hits in the U.S.: ‘Good Lovin’ Ain’t Easy to Come By,’ ‘What You Gave Me,’ ‘California Soul’ and ‘The Onion Song.’ That last one – which might contain one of the strangest metaphors for a world gone wrong – also turned out to be the duo’s biggest hit in the U.K., charting at No. 9. Unfortunately, Terrell and Gaye wouldn’t get the chance to top that feat. In early 1970, during her ninth operation in roughly two years, Terrell lapsed into a coma. She died weeks later on March 16. She was 24.

All Motown staff, with the exception of Gaye, were barred from Tammi’s funeral by her family, who were furious about how the label had treated the singer in what turned out to be her final years. Meanwhile, Gaye drew inward following Terrell’s death, before resurfacing with the social commentary of ‘What’s Going On.’ A significant departure from the Gaye/Terrell hits in terms of topical lyrics and serious tone, the landmark album was reportedly inspired by the turmoil Gaye experienced following the loss of his singing partner.

Listen to Marvin Gaye and Tammi Terrell’s ‘Good Lovin’ Ain’t Easy to Come By’