They are part alike because they are bats but the Vampire bat cuts a hole in cows, horses, and pigs why they are sleeping and lick the blood and the Fruit bat eats fruit.
Most species of flying-fox (fruit bat) have one young a year for a part of their life span. Very occasionally twins are born but their is a low success rate for survival of both twins.
http://www.batworld.org/adopt_a_bat/adopt_a_bat.html and other places... check animal rescue things or just google exotic animal dealers in your area.. make sure its legal in your area to keep them...