Q: Family member unable to access audio books on my family sharing account

Not sure if audiobooks are included in family sharing, they've only just become available for redownloading from the store - this page, What types of content can I share with Family Sharing? - Apple Support, doesn't mention them (it says 'Books from the iBooks Store', don't know if that includes audiobooks). Does audiobooks show as an option if the family member selects your account in the Purchased tab in the iBooks app on their iOS device or Purchased section on their computer's iTunes ?