From 8-year old Hilda’s diary:

It was a very nice party but I like it better when we just visit Lizzie and sit with the nuns. Some of the children did sing and some danced with a basket of flowers that they threw about on the stage. Then a fat lady, in a white and gold dress, sang a song about a lily. And a fat boy in a sailor suit recited a poem about a boy who stood on a burning deck of a burning ship. But why would a boy stand there instead of running away? Well, when everyone got finished doing everything, the fat lady came to the front of the stage and said that now we would all sing together. I didn’t know the words of the song, but they were in English and it sounded as if it were about a cross-eyed bear called Gladly. I wish we could sing songs in English in my Sunday school.

Hilda was certainly not the first or last to mishear the hymn (called a mondegreen) — there are photos and videos of “Gladly the Cross-Eyed Bear” and even a mystery novel. The boy probably recited a poem entitled “Casabianca”.