Every trip we have seen the White Rabbit, the first time he was on the now defunct Epcot holiday bus. Since then he has always been by the Mad Tea Cups ride.
The White Rabbit is one of my DS5's favorites. He calls him his best friend at Disney. When we first saw him, we had been waiting for the Epcot bus to arrive, DS (3 at the time) got a bit grumpy for having to wait. The bus arrived all the characters piled out, and DS decided he didn't want to see anyone! We asked him if he was sure and he said yes. Now the White Rabbit was in earshot of this, he came over to us and tried to cajole our son a bit, which cheered DS up a little. We took a picture, then the WR took DS by the hand and went round and introduced him personally to all the other characters (about 5 or so) WR would sign autographs and pictures while he waited for our DS, the take him to the next character. My DS was over the moon! It was the sweetest thing to do. It wasn't busy, as I was a little worried that the WR would get in trouble from his handler for winging it a little, but it was so great for DS. We always have to seek WR out at WDW now, just to say hi! WR always gets a huge hug and a "I've missed you"