There have been so many things over the years...
Everyday things that I find amusing:
Rowdy does these "poses" in the evening. She will contort herself into some funny position and wait for me to comment, then change to another. My favorite is her "angel pose" where she puts her wings straight behind her, and even sometimes puts a key ring on top of her head like a halo. Sometimes she will sit with a bell on top of her head like a hat.
Pete's laugh. He had the loudest, funniest laugh! I also like when he hangs upside down and flutters his wings. I have to yell, "Batman! Batman bird!"
Merlin's sound effects crack me up. Especially when she says, "How are you?" in that monster voice. Yesterday she said, "Allllrrriiiggghhht" in a funny voice, too.