That is true...Motown being a "family" type organization, which I've mentioned before... would see singers hanging around and a producer could decide that he wanted to add some voices to a project going on in studio A and recruit singers, musicians, or even support people like hand clappers to come in and help with the session. That said... The Andantes and The Originals tended to be the "go to" guys when formal background voices were needed...
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