minipig cafes – one location better than another? and do they always have piglets?

My son desperately wants to visit a mipig cafe when we're in Tokyo in early October.

I read that the Meguro location on a weekday afternoon is the best option for a more quiet visit, as opposed to the constanlty busy areas of Asakusa and Harajuku. It's also a bit cheaper, which is nice, as we're planning on doing so much that I like the idea of saving a bit of money where I can.

Now, I hope this isn't a dumb question: But do they always have piglets in all cafes? What do they do with them when they get bigger? And how do they always get a stream of fresh piglets coming in? lol

I'm asking because I read a review of the Meguro store where they pigs were quite a bit older and hence, more aggressive. Something I'd like to avoid with my son.

Thanks!

PS I know that they aren't the best thing to support from an animal welfare standpoint, but that's a discussion I'd like to keep for another day, thanks.