Did the sows have litters?
Ours usually did and only my grandfather would feed them.
He wouldn't let the grandkids or gramma near them.
The boars didn't get to live long enough to grow huge tusks since they became sausage every Thanksgiving day *but* I've been around old boars with 7" tusks.
They can be nasty.
Back when I was doing crafts for bikers the local stock sale guys would give me the tusks they'd cut off the hogs before they auctioned them.
I have some pretty cool ones stashed around here somewhere.
I used to have a nearly 2/3 of a circle tusk I kept on my keychain until I dropped the keychain and the tusk shattered on the concrete pavement.
Pigs are very, very clever.
You're fortunate that yours were apparently amiable, as well...:)
The sows were almost always having litters. They were very friendly, and were usually trying to get my attention so that I would scritch their tummies. They loved that. Their eyes would roll up in their heads and they would pass out completely.
One of the sows went insane (because of wild dogs killing two-thirds of one of her litters), and that sow would attack any non-pig in the pen. I really had to keep an eye out for her. She lived by herself (and litter) up in the wooded section of the pig pen, instead of the sheds with the rest of the sows. If she saw me in the pen, or anybody else for that matter, it was a race to the fence. That one would kill you if she caught you.
We had one truly massive boar. He was so big that he couldn't mount the sows. They would collapse if he tried. He dug a huge hole, and would push them over to the edge of it and knock them down at the top of the hole. Then he'd stand in the hole with his back feet, and on the top of the hole with his front feet, with the sow on the edge of the hole. Needs must, with a sow in heat. Didn't seem to bother the sows any.
He was mean to everybody but me. I brought the food, and he was very attached to his food supply. He loved me, and even let me scritch him down occasionally. He was taller than I was: I couldn't see over his back. When we finally had him butchered, he had 4-inch tusks, and dressed out at 850 pounds.