I have eleven grandchildren aged from 14yrs. down to eight months. They all love my Kunes and I have never found the pigs more than gentle.
HOWEVER!!!!!!! Pigs are not sensible, thinking beings and a small hand is no different to an apple in their eyes and they will, albeit accidentally, give a hard bite. So, scratching of backs and the backs of ears is lovely but I don't let the tinies hand-feed and the older children have learnt how to give a banana sensibly
My pigs have also, very easily, learnt to sit for a treat, even the boar