‘The Partridge Family’: 11 Secrets You Never Knew About The Musical Show

Though much about the family was fictional, including everyone's vocals on the songs other than Shirley Jones and David Cassidy, the two musical actors also shared a relationship as stepmother and son.

Unfortunately, after the series catapulted to success, Shirley's marriage to Jack Cassidy (photographed here with their two sons Shaun and Patrick) came to an end when the character actor's jealousy became too overwhelming.

David has also gone on record noting his father's issues with anger and alcohol, taking his jealousy out on his teen-idol son as well.

The young actor was known for his troublesome antics on and off screen, but at home he was reportedly the victim of physical and emotional abuse from his father. At one point, things got so bad for him that his co-star Dave Madden (who played the band's manager) took him into the shelter of his own home.

Bonaduce still admits that he owes a lot to the kindness he received from Madden.

After starting her career as a teen model, Susan Dey struggled to cope with the sudden rise to fame while filming the series and began drastically restricting her diet.

She would occasionally show up to set with orange fingertips from only consuming carrots. She plummeted to a terrifying 92 lbs. before young Bonaduce's disgusted reaction to seeing her as little more than skin and bones in a bikini made her realize things had gone too far.

That, or it didn't bother them to see the second-youngest Partridge sibling's role recast after the first season, replacing brown-haired Jeremy Gelbwaks with the blonde Brian Forster for the remainder of the series. The network received no mail regarding the change.

According to the rest of the cast, Gelbwaks' exit had to do with his personality clashing with pretty much everyone on set.

When their biggest hit, "I Think I Love You," was released on The Partridge Family Album in 1970, the quirky tune went straight to the number one spot on the Billboard charts and sold more copies than one of the final Beatles singles, "Let It Be."

Despite becoming a major hit, selling out records, topping the charts, and seeing their faces on tons of merchandise over the years, their record company retained most of the profits.

At the peak of their fame, David Cassidy was headlining concerts but only receiving a $600-a-week paycheck from the studio. Luckily, he was later able to renegotiate that when his manager realized Cassidy was underage when he signed the contract.

Desperate to escape the cookie-cutter image of a squeaky clean teen pop idol — and to make a point to the studio heads still holding back the profits at the time — Cassidy shocked everyone by agreeing to appear seminude on the cover of Rolling Stone magazine.

The accompanying interview also had the actor admitting to riding around the back of a car in New York City "stoned and drunk."

While Cassidy performed a solo show at London's White City Stadium in 1974 during a break from filming the series, a sudden stampede toward the stage caused 30 young attendees to be crushed against the gate. One of them, a 14-year-old named Bernadette Whelan, died from her cardiac injuries four days later.

Cassidy said the tragic event would haunt him for the rest of his life.

Dey harbored a crush on Cassidy throughout the series' run, but he never reciprocated the feelings until deciding to give it a shot once they'd wrapped the show in 1974.

It was a brief affair, though Dey felt Cassidy ultimately described it in far too much detail in his autobiography. The two are not on speaking terms today.

The Cowsills — a family band consisting of six brothers, a sister, and their mom — had a string of hits, including 1967's "The Rain, the Park & Other Things," and became the basis for the idea of a fictional version. Shirley Jones has referred to the group as "the real deal."

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