Nope, that's not Christie Brinkley's much younger sister -- that's the model's 15-year-old daughter, Sailor Lee Brinkley-Cook!
The mother-daughter-duo are Bella NYC's summer issue cover girls and it's pretty crazy how identical the two look.
The former supermodel shared the news via Twitter that her beautiful daughter will follow in her famous footsteps and try her hand at modeling.
The 59-year-old tweeted, "Sailor, Chester [the dog] and me on our first cover together since Sailor started modeling!," along with an image of the mag on Monday.
The ladies both look lovely wearing their hair in loose curls and sporting comfy-casual sweaters.
In the accompanying interview, Brinkley even gets a little emotional talking about her daughter.
"It seems like just yesterday that I was holding her in my arms," she explains. "And now she's standing next to me, this radiant beauty."
We think Sailor definitely will have a career in fashion -- especially if she ages as gracefully as her model mom!
Click "Launch Gallery" above to see more model kids!