Hi Genevieve!
Thank you for bringing your question to the Disney Parks Moms Panel. I was a big Winnie the Pooh fan myself as a little girl, and while Piglet is your sons favorite, I was always partial to Eeyore!
For any fan of the Winnie the Pooh characters, my first recommendation would be to ride
The Many Adventures of Winnie the Pooh attraction! This attraction is friendly for all ages and heights and I think your son will really enjoy being able to see Piglet here. Another place to capture a great memory is at a stationary photo opportunity within
Disney Springs. There is a small log that you can climb up onto to take a picture with a Winnie the Pooh, Tigger and Piglet statue. If your son wants to meet Piglet in person, the only option would be within the Character Dining Experience you mentioned at
The Crystal Palace. If he's only partial to Piglet that would be your best option, but if you think you could satisfy him with Winnie the Pooh and Tigger, they also meet at
The Thotful Spot in Fantasyland.
I hope this helps in planning the day for your little one! Please come back if we can help in any other way.
-Lindsey