Final answer:
The text does not provide specific details about what Ruth Behar's grandparents let her do in their fabric store, but it commonly involves activities like embroidery or crochet.
Step-by-step explanation:
The text does not specify the specific actions Ruth Behar's grandparents allowed her to do in the fabric store.
However, when discussing the theme of textile and fabric work in literature, we often find characters engaging in activities such as embroidery, crochet, or other forms of needlework.
Without explicit information from the question's reference, we cannot definitively state what Ruth Behar's grandparents let her do in the store.
It is possible they involved her in similar textile-related tasks or allowed her to observe the store's daily operations.