Gwen Stefani left her fans in disbelief on Thursday when she shared a photo of her rarely-seen sister Jill.
The Voice star took to Instagram with a sweet snapshot of the pair in honor of Jill's birthday and the family resemblance was clear to see, with Gwen and Jill sporting near-identical smiles and sharing many similar facial features.
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In the image, both women are wearing floral garlands around their necks and large flowers in their hair while beaming at the camera – and it's not hard to see why many of Gwen's followers called them twins.
"Happy b day to my sister @madolivemm love u!! sissy [red heart] gx," Gwen captioned the photo.
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Her followers were quick to react, with one commenting: "So different, yet so the same… Two sisters, only have their parents to blame!!! Happy Birthday, Jill."
A second replied: "You could be twins!" A third added: "Oh my goodness. You two look so much alike."
Gwen and Jill look so alike
Alongside Jill, Gwen has two other siblings, Todd and Eric, and they are all very close and talented.
Younger brother Todd is a film and video producer and has previously worked with Gwen. He was a camera operator for her 2006 concert video, Harajuku Lovers Live, which is a recording of one of Gwen's concerts during her Harajuku Lovers Tour in 2005.
Their older brother Eric is a successful animator and was even in No Doubt with Gwen during the early years, with the duo co-writing one of the band's biggest hits, Don't Speak.
Gwen's brother Eric is her 'hero'
He left the band to focus on a career in animation and Gwen opened up about her love for him during an interview with Seth Meyers on Late Night.
She said that Eric was the one who "taught me everything I know" about music. Gwen also added: "My brother is, like, my biggest hero. He's an amazing artist and talent."
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