Well, "Ovoid" is a shape, and she's probably in that shape. Given her ovoid shape and short legs, that 20 minutes was probably 3/4 of a mile. Even before I started walking for exercise in 2011 I could have done better than that without being particularly tired. She should work up to walking
this 5K event in under an hour and a half (even with her short legs that should be
very doable!). She'd be in the last starting corral (BTDT, got many T-shirts), but maybe seeing 1000s of fit people would inspire her (and maybe even her bird would eat healthier).