I am struggling to pass a attribute value from a parent component (Lookupclean) to a child component (flowFooter). I am trying to pass the value to the child component in order to validate that a value has been entered in a field. The parent component is a lookup field (necessary with flow) and the child component is a footer bar. The idea is that the next button wont fire unless a value is entered. However i can not seem to pass the value from Parent to Child. 

Parent Component (LookupClean):
Component

<aura:component implements="flexipage:availableForRecordHome,force:hasRecordId,lightning:availableForFlowScreens">
   
    <aura:attribute name="object" type="String" default="Offers__c" access="public"></aura:attribute>
    <aura:attribute name="lookupField" type="String" default="Opportunity__c" access="public"></aura:attribute>
    <aura:attribute name="selectedRecordId" type="String" access="public"></aura:attribute>
    <aura:attribute name="parentAttribute" type="String" default='test'></aura:attribute>
    <c:flowFooter childAttribute="{!v.parentAttribute}"/>
  
    <lightning:recordEditForm objectApiName="{! v.object }">
    	<lightning:inputField fieldName="{! v.lookupField }" aura:id="field" onchange="{! c.handleOnChange }"/>
    </lightning:recordEditForm>
       
</aura:component>

Controller

({
    handleOnChange : function(component, event, helper) {
        component.set( "v.selectedRecordId", event.getParams( "fields" ).value );
         var ally = component.find("field").get("v.value");
        console.log(ally);
        component.set("v.parentAttribute",ally); 
        console.log(component.get("v.parentAttribute"));
    }
})

Design

<design:component>
    <design:attribute name="object" />
    <design:attribute name="lookupField" />
    <design:attribute name="selectedRecordId" />
</design:component>

Child Component

<aura:component access="global" implements="lightning:availableForFlowScreens">
        
   <!-- Determine which actions are available -->
   <aura:attribute name="canPause" type="Boolean" />
   <aura:attribute name="canBack" type="Boolean" />
   <aura:attribute name="canNext" type="Boolean" />
   <aura:attribute name="canFinish" type="Boolean" />
   <aura:attribute name="childAttribute" type="String" />
   <aura:handler name="init" value="{!this}" action="{!c.init}" />
   
        
   <div aura:id="actionButtonBar" class="slds-clearfix slds-p-top_medium">
      <!-- If Previous is available, display to the left -->
      <div class="slds-float_left">
         <aura:if isTrue="{!v.canBack}">
            <lightning:button aura:id="BACK" label="Previous"
               variant="neutral" onclick="{!c.onButtonPressed}" />
         </aura:if>
      </div>
      <div class="slds-float_right">
         <!-- If Pause, Next, or Finish are available, display to the right -->
         <aura:if isTrue="{!v.canPause}">
            <lightning:button aura:id="PAUSE" label="Pause"
               variant="neutral" onclick="{!c.onButtonPressed}" />
         </aura:if>
         <aura:if isTrue="{!v.canNext}">
            <lightning:button aura:id="NEXT" label="Next" 
               variant="brand" onclick="{!c.onButtonPressed}" />
         </aura:if>
         <aura:if isTrue="{!v.canFinish}">
            <lightning:button aura:id="FINISH" label="Done"
               variant="brand" onclick="{!c.onButtonPressed}" />
         </aura:if>
      </div>
   </div>
</aura:component>

Controller
 

({
   init : function(cmp, event, helper) {
      // Figure out which buttons to display
      var availableActions = cmp.get('v.availableActions');
      for (var i = 0; i < availableActions.length; i++) {
         if (availableActions[i] == "PAUSE") {
            cmp.set("v.canPause", true);
         } else if (availableActions[i] == "BACK") {
            cmp.set("v.canBack", true);
         } else if (availableActions[i] == "NEXT") {
            cmp.set("v.canNext", true);
         } else if (availableActions[i] == "FINISH") {
            cmp.set("v.canFinish", true);
         }
      }
   },
           
   onButtonPressed: function(cmp, event, helper) {
       var label = cmp.get("v.childAttribute");
 	   var isDefined = !$A.util.isUndefined(cmp.get("v.childAttribute"));
       console.log(isDefined);
       console.log(label);
          
         if (label) {
             // Figure out which action was called
      	     var actionClicked
 = event.getSource().getLocalId();
      	     // Fire that action
     		 var navigate = cmp.get('v.navigateFlow');
      		 navigate(actionClicked);
         } else {
             alert('Last One 10000');
         }
     }
     

})

here is a screenshot showing the two console logs on my Lookupclean after the field is filled

Here is a screenshot showing the two additional console.logs when i press my flowFooter button. the attribute is undefined

Any ideas?