As it often happens when animals are given as gifts, Fox’s mom was not prepared for him and didn’t have the time or energy to devote to him, which is probably how he ran away unnoticed. Giving any sort of animal as a gift is generally a bad idea unless the recipient knows about it and is prepared for their new pet. Surprising someone with a pet, unfortunately, often leads to lots of unwanted animals ending up at shelters.
Luckily, little Fox was found by the right people. He was a little dehydrated from living on the streets without access to water, but other than that, was in pretty good shape.