Baby, like a bug that I mushed in

The story:

I was singing loudly to myself, thinking no-one was in the house, when my younger sister walked down the stairs. As if it wasn't embarrassing enough that I'd been singing loudly and painfully, she managed to say through her gales of laughter that I'm such a silly bum, and when she'd composed herself revealed the real lyrics. then proceeded to call up her friends and tell them all about it. oh the shame!