When Selena Gomez's mom gave birth last year, Selena was super-excited to be a big sister. Now, she gets to step into the older sis role once again!

Her father Rick Gomez surprised everyone by posting a photo celebrating the birth of his newborn daughter Tori Gomez, who was born about a month ago — and nobody realized it.

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He said, "Time flies….It seems like just yesterday we found out we were having a baby. And now our baby Tori is 1 month. So blessed and grateful."

Tori looks adorable! While Selena hasn't posted anything about her new sis, we can't imagine she'd be anything but happy to have another little sibling.

Are you surprised that Selena has another baby sister? Spill all your feelings in the comments!