Mini pigs are pigs that have been selectively downsized over many generations in order to produce a pig that stays small, and can therefore make a great indoor pet. A mini pig will generally grow 12-16 inches and will reach 25-65 pounds; similar to a smaller dog. Mini pigs need a lot of attention; they do best with a companion pig to keep them company. They work well for people with allergies because they have coarse hair, called bristles, rather than fur. Like their larger counterparts, mini pigs enjoy a roll in the mud outdoors every so often.