Where has the time gone? Jamie Lynn Spears' daughter Maddie is all grown up and celebrating her very first day of third grade!

The country singer and younger sister of Britney Spears shared the back-to-school photo of her eight-year-old daughter — and fans could not get over the transformation.

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"Wow! She is growing up so fast!!" one follower wrote while another added, "I can't believe she is Already in the 3rd Grade wow how time flies by Fast!!"

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3rd grade🍎👧🏼📚📓

A post shared by Jamie Lynn Spears (@jamielynnspears) on

And commenters were also quick to notice that thanks to her school uniform she looks just like her famous aunt.

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The Zoe 101 actress was just 16 years old when she welcomed her daughter with then boyfriend Casey Aldridge. She tied the knot with actor Jamie Watson in 2014.

For more celebrity kids all grown up, check out the gallery below!