A mother was reading a book

A mother was reading a book about animals to her 3 year old daughter:

Mother: ‘What does the cow say?’

Child: ‘Moooo!’

Mother: ‘Great! What does the cat say?’

Child: ‘Meow.’

Mother: ‘Oh, you’re so smart! What does the frog say?’

And this wide-eyed little three-year-old looked up at her mother and replied, ‘Bud.’