updating componentwillreceiveprops so that it is flexible for a usecase where youre updating the props passed down to a child state (i.e. you favorited a card and added to parent state and you're passing down that state to child as a prop) after an action and you dont want the cards to restart

CardStack.js

@@ -136,9 +136,13 @@ export default class CardStack extends Component {
   }
 
   componentWillReceiveProps(nextProps){
-    this.setState({
+    if (nextProps.children !== this.props.children) {
+      this.setState({
       cards: nextProps.children,
+      cardA: nextProps.children[0],
+      cardB: nextProps.children[1],
     });
+    }
   }
 
   _resetCard(){