Anniversary of What?

Mommy and Daddy had an anniversary yesterday. This was all very vague to me, as they never said of what it was an anniversary. Perhaps they did tell me while they were showing me photographs of themselves, and younger people who looked somewhat similar, but I was not giving ear to what they said as I was constantly attempting to find myself in the photographs. Either way, I could tell that this was a day to celebrate, and not a day to nap. So I napped in the morning, and refused to later. This may have soured my mood somewhat, but it was all worth it, or so I thought: they did nothing spectacular the entire day. Finally, they brought me with them on a carriage ride, during which I fell asleep. When I awoke I found myself at Cousin Hendrick's castle, and Mommy and Daddy disappeared. Perhaps this was the celebration to which they were referring, but I see very little difference between this and many other days. I quite enjoyed myself playing with Cousin Hendrick. When they returned we ate some dessert and went home. All in all it did not end up being as exciting as I expected, which makes me nearly regret being so incorrigible with Mommy and Daddy all day. 

Nearly.

"Do you know to whence my parents went?" asked I.

"What's a whence? And why do you talk as if you're so special? You're younger than I am!" protested Cousin Hendrick.

Therefore I forcibly acquired his toy in retaliation.