Animals have a certain temperament when they are born, but like humans, they also learn their behaviour as they grow and so not all animals will exhibit the same behaviour.
Effectively, how they have been treated will have a huge bearing on how they react in certain situations. It is very rare to see a squirrel and a human become good friends. Squirrels are very skittish nervous creatures, and even those that have grown up in the city are very wary of mankind. I have rarely if ever seen a squirrel eating from a human’s hand.
But as I said a lot of this is learned behaviour, keeping yourself safe from perceived predators. When the gentleman from Poland in this video found a baby squirrel at the bottom of a tree dying, he took pity on it, caring for it and effectively becoming a surrogate parent. As the squirrel has known nothing else, he now has absolutely no fear of humans and is totally dedicated to his owner, as this touching video below demonstrates. It just goes to show that with some love affection and dedication, animals and humans can form perfect relationships, even in the most unlikely of circumstances.