S-M-I-L-E
Tune: Battle Hymn of the Republic, a.k.a. John Brown's Body
As recorded by Ed McCurdy on “Children’s Songs,” 1958.

Oh, it isn't any trouble just to S-M-I-L-E.
It isn't any trouble just to S-M-I-L-E.
So smile when you're in trouble;
It will vanish like a bubble
If you'll only take the trouble just to S-M-I-L-E!

It isn't any trouble just to G-R-I-N-grin.
It isn't any trouble just to G-R-I-N-grin.
So grin when you're in trouble;
It will vanish like a bubble
If you'll only take the trouble just to G-R-I-N-grin!

It isn't any trouble just to HA-HA-HA-HA-HA.
It isn't any trouble just to HA-HA-HA-HA-HA.
So HA-HA when you're in trouble;
It will vanish like a bubble
If you'll only take the trouble just to HA-HA-HA-HA-HA!

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I also do that last verse as L-A-U-G-H. Why not? Great song, nice poem. And now it's a music thread!