Looks like the Alexa Echo Dot - Kids Edition (by Amazon) has been recently released. Watch the video from left menu. They also announced the FreeTime feature (free and paid) .
We like our 1-year old Echo Dot. So much so, we decided to go Multi-Room.
Now we have a Echo Dot, Echo v2, and a Echo Plus Hub ... one of each. Yes, while music sounds OK on a Dot ... I think it sounds much better on the larger models.