Our Sandy has never barked. I finally got brave and used a seam ripper to carefully open up his tummy and take out the sound box.

He takes 3 size AG13 batteries. I was at Walmart tonight, and in the toy section they had a little set called the "Interactive Learning Replacement Battery Kit" wich is for electronic books and toys. It was $2 and included 3 batteries, a screw, and the cutest little bitty, doll sized screwdriver.

I was able to change Sandy's batteries with no trouble. I put the box back inside, stitched up the opening and Sandy is good as new.

If your Sandy has stopped barking, it might be worth looking into.