“Living with Klinefelter Syndrome (47,XXY), Trisomy X (47,XXX) and 47,XYY” by Virgina Isaacs Cover is a very good book, which explains Triple-X on page 107 ff. in a very good and compact way.
The book can be downloaded for free!
“Elizabeth and her Extra X” by Arlie Colvin explains Triple-X very good to children
Elizabeth and Her Extra X read by Erin Torres: https://youtu.be/3_ycENpOX3Q
“Olivia & Bun-Bun: And The Extraordinary Extra X” by Nicole Browning Ph.D. and Daryna Pazenko is a new book for children
Three Baby Kisses blogs on Instagram in English