Warning Spoilers through Devil's Due.
Petey in Progress V3 by (C) Nestor Menar used with permission.
Petey is a small gliding lizard bird first a pet of Rebecca Anne McDonald, then Sandra Tucker Reddy, then Dennis Silva. Last seen under Isak Reuben's care in Devil's Due.
Dennis Silva and Petey by Nestor Menar AKA Snoeplau "Silva and Petey" He writes "... the finished drawing most probably in my second character sheet (think of it as an illustrated version of the "Cast of Characters" list in the books). …" Posted with artist's permission.
Petey makes his appearance in Rising Tides. Able Cook who said "Why, it looks like an archaeopteryx!"
Described as "The lightly feathered creature sniffing its way skeptically down the falls had stirred his interest. It wasn't much bigger than a cat, with a long neck and toothy head just like any other lizard bird they'd seen, but its abbreviated wings and long, feather-vaned tail more suited to gliding than flying. Silva chuckled as the light improved because the thing was colored predominantly greenish blue and yellow." [R T PB p. 310.]