She had been expecting some sage advice or perhaps a warning about the boy or even the men she had been speaking with earlier and was a bit surprised the barkeep would ask a stranger to run an errand for him.  

"I apologize.  I have another matter I must attend to after getting a meal into this one," she said, indicating toward the boy.  She was worried that if she delayed too long, she may not find the Count in the Mage's library. 

But she did hate to say no when someone asked her a favor, so quickly added.  "Once my other affairs are in order, I'll check back to see if you are still in need."