Imagine if it turned out to be a current member of Congress that you were sick of.

"Dear Senator Grassley,

Congratulations on your 100th birthday.

Please just retire already. Why are you still here? What the hell are you doing? It's pointless. It's all pointless. Stop it! Go do something fun. This can't be fun. Jesus, is this what I have to look forward to in my old age? Are you even allowed to eat cake anymore? I mean, hell, you're 100 anyway, why not? Farting too hard could kill you at this point, may as well enjoy what's left of your life. So please retire.

Yours Sincerely,

[Insert Name of President in 2033 Here]"