With four delightful Benny and Penny titles already gallivanting around out there, Hayes' work is a prime example of TOON's high-level product. ... Hayes, as always, strikes exactly the right balance, allowing his characters to be both moody and reasonable, scared and courageous, appealing to young readers both as surrogates and role models. His art similarly hits the sweet spot dead-on, with mysterious shapes that are never too menacing, rounded and soothingly furry figures, and delicately rendered backgrounds filled with meticulous detail. His warmly classical picture-book technique never fails to be both animated and engaging as well.
--Booklist

Hayes' colored-pencil panels keep their sunny charm even in the fog. These sweet sibs show no signs of growing old--thank goodness.
--Kirkus Reviews

The mouse siblings return for another stellar beginning reader adventure. ... Geoffrey Hayes strikes the right balance between comics-style panels and words that novice readers can figure out by sounding them out or by using visual clues he provides. He also taps into the emotional life of young children through Benny and Penny's interactions, getting the dynamics down with precision and authenticity. ... Here's hoping for more from this loving mouse family.
--Shelf Awareness (starred review)