When your actual energy amount exceeds maximum energy level (for example, the energy bar shows 190/87), the family cannot eat. There is a solution - you need to make the family hungry again. Reduce energy by chopping down resource objects, exploring the islands and completing the game tasks. Eventually your energy will decrease below maximum level, and you can feed the family again!
 
Do not worry, the food tasks can wait, nothing can stop you from progressing in the game!
 
Tip: if you want to collect a lot of energy, feed the family first and collect the energy from the chests/merchant/shaman/gifts/energy packages afterward.