No, not the Law and Order music.
"Bum bum" is Lavender's ubiquitous word, or maybe I should call it her prototype word. It's the word from which almost every other word she says is derived. For instance, "pom bum" is pumpkin, "bu' buh" is buckle, and "bom bom" is bottle. Usually. There's a certain amount of fluidity between words, and most of my Lavender Comprehension comes from context. Still, it feels really good to be able to say that my baby daughter speaks and I understand her. I can't describe how dense and inept I feel when I have a child making urgent, repeated requests of me that I cannot for the life of me translate into some form of useable English. I'm sure Lavender would liken the experience to talking to a dog: she asks a question that seems perfectly clear; I cock my head to one side and prick up my ears, or wag my tail and bark. So now, finally, I'm able to make sense of most of what she says. Most of it is "bum bum," and that's just fine. It's better than fine. We're communicating.
Here is a list of Lavender's words that sound almost indistinguishable from "bum bum." For some of them, being on this list makes a lot of sense. For others, I'm dying to see how her brain made that leap, but in the end I'll probably never know.