I'm using it with a smaller child, she loves trying to keep the notes going.

It's also a well-established fact that many of the most famous musicians in history, from the Beatles to Tchaikovsky did not have perfect pitch.

Perfect pitch can even be a negative factor in one's musical training. For example, in musical theater, cabaret, and jazz, transposition is a necessary skill. Singers routinely ask the accompianist (on piano) to move the key up or down to match their vocal range. I have heard anecdotally that perfect pitch actually makes it difficult to transpose, because if you learned a song in a certain key, the transposed version sounds like a different tune.