Is it too late for my estate to lay claim to one of the verses in that song?

"Big Fleas have little Fleas
Upon their backs to bite 'em,
And little Fleas have littler Fleas,
And so ad infinitum

And those big Fleas themselves in turn
Have bigger Fleas to go on,
And bigger Fleas have bigger Fleas,
And bigger still ... and so on"

J. Swift.