WATCH: Little girl can’t deal with her baby brother growing up

For most kids, growing up isn't exactly something they look forward to. When I was a little, I remember obsessing over the "I Don't Wanna Grow up, I'm a Toys 'R' Us Kid" song. Just the thought of no longer being able to play with Barbie dolls and video games seemed scary to me. But sometimes watching someone else grow up, like our kids or nieces and nephews, can be even harder. For one 5-year-girl from Phoenix, Arizona, the thought of her 3-month-old baby brother growing up just makes her hysterical–and the adorable-ness that ensues is all over the internet.

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Sadie Miller was completly devastated when she discovers that her cute baby brother will one day grow up. The poor thing is seen in the video crying up a storm while holding her little brother Carson and kissing his head. "He's so cute, and I don't wanna die when I'm a hundred," she says in a fit. The video went viral after her uncle uploaded it to YouTube on Monday and it's been buzzing around the internet ever since.

"She's cried about not wanting to get older herself in the past, but this was the first time she was upset about her brother," Sadie's father, Ryan Miller, told Time magazine. "The funny thing is that this was totally out of the blue–we have no idea what prompted it."

I can't blame little Sadie for being so upset. Her baby brother is seriously adorable, who wouldn't be sad at the thought of him one day growing up? He was all smiles and giggles throughout the entire video, clearly entertained by his big sister's crying. She'll eventually learn with time that growing isn't really all that bad, most of the time anyway.

Embedded content: https://www.youtube.com/watch?v=84DLT4yRcy4

Image via YouTube.com