I am wondering if I can update my apex class to show child records of a child record from the account object.

I have a custom object Bids_Sent__c of an account standard object. The Bids_Sent__c object has a child object  entitled Site_Bid_Details__c. That custom object has a child object entitled Payments__c.  
My Apex Class below is updated to show Account with Bids_Sent__c ad Site_Bid_Detail__c records on my visualforce pdf. But it does not cover the new custom object Payment__c.  I need this to show those child records to show monthly payments if the Site_Bid Detail__c record meets a certain criteria. I'm not sure how to add this to my current class or if this is possible.  

If anyone could help me with this I would greatly appreciate it. 

 

public with sharing class VF_PrintBidPDF {

private Account acc;
   public List<Bids_Sent__c> bidsList {get;set;}
   public Map<String,List<Site_Bid_Details__c>>  bidsMap {get;set;}
   public Map<String,List<Site_Bid_Details__c>>  sbidsMap {get;set;}
   public VF_PrintBidPDF(ApexPages.StandardController sc){
       acc = (Account)sc.getRecord();
       bidsList = new List<Bids_Sent__c>();
       bidsList = [SELECT Id,Add_to_Schedule_C__c,Customer__r.Service_Agreement_Verbiage__c,Site__r.Service_Agreement_Verbiage__c,Service_Agreement_Verbiage__c,Awarded_Date__c,Site__r.Customer_Location_ID__c,Service_Year__c,Site__r.Customer_Account__r.Name,Name,
        Site__r.Name,Customer__r.Name,Primary_Contact__r.FirstName,Site__r.BillingCity,Site__r.BillingState,Site__r.BillingStreet,Site__r.BillingPostalCode,Site_Customer_Name__c,Customer_Name__c,Contract_Start_Date__c,Contract_End_Date__c FROM Bids_Sent__c WHERE Awarded__c =: acc.Id AND Add_to_Schedule_C__c=true  ];
    
          Set<Id> bidId = new  Set<Id>();  
    for(Bids_Sent__c bs : bidsList){
       bidId.add(bs.Id);
}
     
          bidsMap = new Map<String,List<Site_Bid_Details__c>> ();
    for(Site_Bid_Details__c bd : [SELECT Id,IsSeasonal__c, Bid_Name__r.Name,Site__c,Contract_Start_Month__c,Site__r.Customer_Location_ID__c,Cost__c,Increment__c,
    Total__c,Price__c,Scope__c,Bid_Name__r.Service_Type__c,Number_of_Months__c,Retainer_Fee__c,Monthly_Payment__c,UOM__c,Month_Start_Number__c,Month_End_Number__c, Contract_End_Year__c,IsConEndYear__c,IsZone__c FROM Site_Bid_Details__c WHERE Bid_Name__c IN : bidId]){
        
      if(bidsMap.containsKey(bd.Bid_Name__r.Name)){
          System.debug('CONTAINS KEY: ' + bd.Bid_Name__r.Name);
          bidsMap.get(bd.Bid_Name__r.Name).add(bd);
    }  
              
      else { 
          System.debug('CREATE: ' + bd.Bid_Name__r.Name);
          bidsMap.put(bd.Bid_Name__r.Name,new List<Site_Bid_Details__c>{bd}); 
           }
           
    }
          sbidsMap = new Map<String,List<Site_Bid_Details__c>> ();
    for(Site_Bid_Details__c sbd : [SELECT Id,IsSeasonal__c, Bid_Name__r.Name,Site__c,Contract_Start_Month__c,Site__r.Customer_Location_ID__c,Cost__c,Customer__r.Contract_Month__c,Increment__c,Total__c,
    Price__c,Scope__c,Bid_Name__r.Service_Type__c,Number_of_Months__c,Retainer_Fee__c,Monthly_Payment__c,UOM__c,Month_Start_Number__c,Month_End_Number__c,Contract_End_Year__c,IsConEndYear__c,IsZone__c   FROM Site_Bid_Details__c WHERE Bid_Name__c IN : bidId AND IsSeasonal__c = true]){
        
      if(sbidsMap.containsKey(sbd.Bid_Name__r.Name)){
          System.debug('CONTAINS KEY: ' + sbd.Bid_Name__r.Name);
          sbidsMap.get(sbd.Bid_Name__r.Name).add(sbd);
    } 
      else { 
           System.debug('CREATE: ' + sbd.Bid_Name__r.Name);
           sbidsMap.put(sbd.Bid_Name__r.Name,new List<Site_Bid_Details__c>{sbd}); 
           }
        } 
    }
    
    public VF_PrintBidPDF(ApexPages.StandardSetController controller) {
    }
    
    public VF_PrintBidPDF(){
       String myGeneratedFileName = 'SalesforceScool.pdf';
       Apexpages.currentPage().getHeaders().put('content-disposition', 'attachment; filename='+myGeneratedFilename); 
    }

}