The perfect holiday gift for the readers in your family would be a Kindle Book. Usually more inexpensive than other gifts, a kindle book can be easily given to anyone in the world.
"Any Kindle book available for purchase in the Kindle Store can be given as a gift to anyone with an e-mail address. You do not need a Kindle device to send or receive Kindle book gifts, and the recipient can read their gift on a registered Kindle device or any free Kindle reading application." Amazon Website
For more details about giving and receiving kindle books click on the following link:
Kindle Book Gifting