Won't let me upgrade – 100 words for Babies & Toddlers Review

I love this app, but it won't let me upgrade. I have a granddaughter with a speech delay and this app has really helped her learn new words but we need the whole app. Ive tried tapping the owl 3 times and it doesn't work.
Review by Kathy 1982 on 100 words for Babies & Toddlers.