EXCLUSIVE
Crough starred as the tambourine-shaking daughter Tracy Partridge ... during the classic sitcom's run from 1970 to 1974.
She was 52 years old. It's still unclear what caused her death, but a family member confirmed Suzanne's passing and said it was sudden.
Suzanne was married with 2 daughters ... one of whom is getting married this summer.
She last reunited with her 'Partridge' co-stars for an appearance on the 'Today' show back in 2010.
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