Maybe it's the catbird's call? It certainly is varied, cheerful, and entertaining. If you want to listen to it, here's a link to Cornell Ornithology Lab, where they have some recordings. The "song" didn't sound cat-like, but if you click on the "mew call," you'll get the idea for where it got its name.
But then she posted a rare photo of the catbird showing off his "caboose," and a whole new facet of the catbird's personality became apparent! It was like Mammy in Gone With the Wind, pulling up the hem of her faded old housedress to show off the scarlet satin petticoat, a gift from "Mr. Rhett," hiding underneath.
I didn't really do justice to this guy—he needs to be painted "for real," a little more painstakingly on watercolor paper without black lines (and not as a direct copy of the photo)—but it will do for a fast impression. Maybe I'll attempt him again when I have more time, but here's my quick sketch for today—"Catbird Caboose," in honor of Kim Denise!
Uniball pen, watercolor