Aggregate Qry - Use LAST of Non Zero Number

Experts, 

I have an aggregate query as below (and attached file) that returns the LAST record on RATE. 

I need to somehow adjust it to use the LAST of RATE of the non zero number.

You can see the LAST of the rate is 0 for the highlighted one below:

there are 5 records for IDParentfk (refer to the count) and I need to return the Rate that is NOT ZERO.

So essentially, I still need the LAST record but ONLY the LAST of where Rate is NOT ZERO. 

tblFXRollsChild:

5 records. 

I need the 3rd record in this case since its the LAST that is not 0. 

SQL:

SELECT tblFXRollsChild.IDParentfk, Last(tblFXRollsChild.Rate) AS LastOfRate, Count(tblFXRollsChild.IDRollsPK) AS CountOfIDRollsPK
FROM tblFXRollsChild
GROUP BY tblFXRollsChild.IDParentfk;

let me know if there are any questions.  I hope its clear. 

Please see attached sample db