I remember reading this one when I was a little one. I wasn't as young as the piglets, because I remember reading it to myself. But it really is a good one for read aloud.
There aren't many pictures. And what pictures there are are just black silhouette sketches. But I tend to think that's good for children. Preschool is probably the earliest that the magic of their imaginations is enough to get them through a chapter book like this one.