For Elizabeth, the word "datch" translates to "watch." It can mean either the time-keeping piece, or the verb "phrase" as in, "I want to watch what you're doing." When Elizabeth "datches" you, she often uses either a step stool (at home) or a folding step (out at Opa and Oma's - her paternal grandparents).
Tonight Elizabeth and I were reading
The Little Mouse, the Red Ripe Strawberry and the Big Hungry Bear. I pointed to the mouse dragging the (very long) ladder out of the house, and asked Elizabeth what it was. After hearing "moush," I clarified that I was pointing to the ladder, and she answered quickly, "datch." Well, of course, it's something you use to climb up so you can "datch."
Makes sense to me.