Abandoned Kids Challenge - Teenager raising their Siblings [with no money]!

Very interesting concept. :+1:
The game will not let you create a Teen/Child household without an older Sim. BUT there is a way to have a household with no YA/Adult.
Once you have created the household place them in the game. Immediately go to Manage World and select your household. Edit them in CAS deleting the older Sim(s). The game will then allow you to play as long as there is at least one Teen.