Sadie, age 5, has just confronted the fact that her adorable baby brother won't stay a baby forever. His little baby smiles will soon become slightly-less-adorable toddler smiles. And eventually, the icy finger of death will beckon her, her brother, and all of us. Probably when we're a hundred.

But that baby has the right idea: He is not worried about any of this. Look at his cute little smiles!

[H/T Reddit]