I would like to come with some suggestions, however I need some info about your set up.
How do you store your music? (on a hard drive connected to Rasperry Pi or a NAS or ?)
It sounds to me that you only have one touch display with Jivelite but more than one child, were do you want to put the Jivelite control so your children has access to it at the same time??
What music setup does your children have at present ? (bluetooth speakers or a pi with speaker connected or ?)