You may share your ebooks with your family members in the ways that the ebooks stores allow - lending ebooks and sharing accounts.
Moderator Notice
'Sharing' your ebooks in other ways is another word for copyright infringement, and must not be encouraged, supported or condoned on MobileRead.
There is a way you can legally share your Kindle ebooks with others. Get a Kindle, register it to your account, and loan the Kindle. The person you loan it to will be able to download any of your books to the Kindle to read.
Of course, they'll also have access to your Amazon account, so you probably won't want to do this with anyone you don't trust completely.