Change to radio after card is done

I'd like a toggle for my player so that when a card or playlist is over, it automatically switches to the radio. My son sleeps with the radio sometimes but lately he will start bedtime with a story, and when it's over he occasionally hasn't yet fallen asleep and asks us to change it to radio. It's alright that we can do that from the app but it would be nice for it to be a feature.

Thanks!