Victoria's Secret beauty Lily Aldridge discovered her mother was a Playboy model when she was 12 years old after becoming convinced her dad was "cheating" by looking at the raunchy men's magazines.

The stunner, who fronted last year's (14) Sports Illustrated Swimsuit Issue with Chrissy Teigen and Nina Agdal, is the daughter of British artist Alan Aldridge and busty brunette Laura Lyons, who bared all as the Playmate of the Month for Playboy's February 1976 issue.

Aldridge reveals she came across her dad's copy of the adult publication unexpectedly and immediately jumped to the wrong conclusions.

She explains, "My dad was an artist and he had an art studio downstairs. I was rifling through his things and I found a Playboy and I was like, 'Oh my God, dad is cheating on mum with Playboy!'

"I was so upset, I ran upstairs and I told my mum... and she eventually was like, 'Ok, listen...' and she showed me (her photoshoot). I thought it was awesome."

However, Aldridge, who is married to Kings of Leon rocker Caleb Followill, admits she wasn't always so proud to boast about her mother's saucy modelling achievements.

She adds, "I thought it was so cool until high school when all my guy friends started Googling her."

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