Hello, would you please explain to me the words in red?<br/><ul><br/><li>These preppy and practical bags are designed for everything from sports gear to overnights to weekends at Grandma's. </li></ul>I feel like there should be a noun after "grandma's ", like "grandma's house" for example. What exacatly is "Grandma's" here?<br/><br/>Thank you in advance.