Ramayana and Mahabharata traditions are grouped under Itihasa. Puranas are a different literary family containing narratives, devotional material, cosmology and other themes.
A familiar story may appear in a named Sanskrit text, a later regional work or an oral devotional telling. A child adaptation should say which kind of source it follows instead of inventing a chapter reference.
Our reading pathways will connect accessible stories to their source notes and editions. The little-squirrel story in this preview is explicitly labelled a popular later devotional Ramayana telling.