What font size should be used for a children's book?

I’ve been looking around, and so far I haven’t found much. Most places I find also suggest using Comic Sans so I'm hesitant to take their advice.

The book will be for ages 0 — 5, so very young, most likely their parents will read it to them. The page size is 6in x 9in and there’s a good paragraph worth of text on pages that have text. Should the font be the standard size 12 as other books? Or should it be bumped up for kids? How big is to big in that case? Is there a standard for this, or is it mostly guess and check?

This is the first time I’ve illustrated a children’s book, so I have no idea. Any help is much appreciated!