Alphabet obsession

Ryder is hooked on the alphabet lately! He walks around singing it all the time. And I do mean ALL the time--almost as soon as one rendition is finished, the next one starts. He's put his own twist on it though. He almost only starts singing at H. He knows the whole song because if you prompt him with A he'll do the whole thing. But, on his own, it's now, "H I J K L M N O P Q R S T U V W X Y and Z. Now I know my ABCs. Next time won't you sing with me!"