Pig
It wallows because it has almost no sweat glands, and mud is how a pig manages heat. Rooting is a need rather than a habit, and pigs work out how to reach food.
Overview
Pigs cannot cool themselves the way most animals do. They have very few functional sweat glands, so they manage temperature behaviourally instead, and above about 85 degrees F, especially in humidity, an unshaded pig is in trouble. That is what the wallow is for: cooling first, then sun protection, then getting rid of external parasites.
The other constant is rooting. It is not a habit to train out, it is how a pig investigates the world, and a pig with ground will turn it over. Anyone keeping one either gives it somewhere to do that or watches it happen to the lawn.
Temperament
Clever, sociable and extremely good at getting what they want. Pigs solve problems, they remember, and they will test a fence and a person with the same patience.
They are much stronger than they look and they push rather than jump, which is why fencing is low and solid rather than tall. Keep them in pairs, since a pig alone is a bored pig, and expect a mature animal to be a good deal larger than the one you were shown as a piglet.
Care and grooming
A measured pig feed plus greens, weighed rather than offered freely, because obesity in pet pigs is common and it damages joints and shortens lives. In many places feeding kitchen scraps to pigs is also illegal, and it is worth checking the rule where you are rather than assuming.
Hooves and tusks need attention in older animals, and skin needs a look for sunburn, since a pale pig burns in sudden strong sun and a badly burnt pig can go weak in the back legs.
Living and exercise
Strong low fencing, deep shade, and a wallow they can actually get into. Shade is not a nicety in summer, it is the animal's only real cooling other than the wallow.
Give them a dry insulated house with plenty of bedding, ground they are allowed to destroy, and something to occupy them. Pigs live 12 to 20 years, which is far longer than most people expect, and rehoming an adult pig is genuinely difficult.
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