J.P.
Hi S.,
I like smilebox.com.
You'll need to download their free software. If you chose not to pay a fee, then your sister will get a little advertising on the side of her email. I have only done it this way so far. I am thinking about becoming a member because their are cool bonus features then. Non-members can still upload photos to add to their cards. I've even inserted my personal photos into on line stationary for memory books. I hope you enjoy the website. I am glad I stumbled upon it about a year or so ago.
There are so many occassions, cards, etc... to select from.
J.