It's not wrong, but it's not a natural way of speaking. I enjoy children's stories because of the rhythm.
For example, the Little Red Hen asks who will help her bake the bread.
"Not I," barked the lazy dog.
"Not I," purred the sleepy cat.
"Not I," quacked the noisy yellow duck.
This works in the read-aloud story "The Little Red Hen" because it propels the story and listeners get caught up in the rhythm. But as the great theologian Paul wrote, "Now that I have become a man, I've put an end to childish things" (1 Corinthians 13:11b CEB).
"What do you want?" Mary asked.
"I don't know," Kelly answered.
Sounds natural and it flows. Good writing is natural and keeps readers focused on the dialog and not on the writing style.
The more natural my writing, the easier it is for readers.