Robert Louis Stevenson's
stepson, Lloyd, described Henley as
"..a great, glowing, massive-shouldered fellow with a big red beard and a crutch; jovial, astoundingly clever, and with a laugh that rolled like music; he had an unimaginable fire and vitality; he swept one off one's feet".

In a letter to Henley
after the publication of Treasure Island,
Stevenson wrote, "I will now make a confession.
It was the sight of your maimed strength and masterfulness that begot Long John Silver...the idea of the maimed man, ruling and dreaded by the sound, was entirely taken from you".