stable boy 
noun
A boy or man employed in a stable.They hurried Down the hall and through the great entrance over to the Royal Stables where two stable boys had their horses ready....
- From that day on, he lived with the Ashfords, tending the stables as a stable boy until he worked his way up to the master he was presently.
- Krista looked back towards the stable and saw the stable boy sweeping and tripping over himself.