When I first got my Kindle Paperwhite, my then 6-ish year old nephews were enamored with the idea of a book you could read in the dark. I made them their own folder and they filled it with books, but every night for months on ends, we read this together. I think I can recite this silly alphabet in my sleep. Even now at 16, they still ask if this book is on my Kindle and then they laugh.
I've seen a lot of reviews talking about how this isn't a good learning tool, but I don't think it's meant to be. I think it shows your children(or nephews in my case) that being silly for silly sake is ok. That you can find joy in a way that makes no sense to anyone else and that's ok.
You know you've done something right Sprogling, when 10 years later, they still ask for your book.
When they've become too grown up for everything else, but they still wanna laugh at this.
Well done you.