Ah, sisterly love.

Though they might not always get along, Dance Moms veteran Maddie Ziegler took to Instagram to share a cuter-than-ever throwback photo in honor of her younger sister Mackenzie's birthday.

"Happy birthday to my amazing little sister! As much as you annoy me, I love u so much," she captioned the sweet pic.

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The girls have grown up quite a bit since they first graced our television screens back in 2011. Click through to see how much Mackenzie and the rest of the cast has changed!