Greetings, Joseph!
First off, I just want to say what an awesome cousin you are to worry about Rosalie! There are several things you can do to help her feel more prepared. For starters, you could pull up pictures from past Disney vacations, or even images online featuring Donald Duck doing meet-and-greets.
Once she has arrived at the parks, I wouldn’t force any interactions right away. Stroll by Characters from a distance so she can observe and understand what to expect. You may even want to let her pick out her own autograph book and pen to celebrate the occasion!
When she does feel ready, you could mention her concerns to Donald and his helper, so he knows not to get too close. If Rosalie simply isn’t ready for an up-close interaction, she can wave to Donald Duck from a safe distance during
Mickey’s Soundsational Parade. Another option is a Character Dining experience, such as
Donald Duck’s Seaside Breakfast at Disney’s Paradise Pier Hotel. Perhaps seeing Donald in a quieter setting may help her feel more comfortable. Another Donald-inspired spot is
Donald’s Boat in Mickey’s Toontown – she’ll love climbing all the way to the top and spinning the Captain’s Wheel!
Lastly, I’d recommend
downloading the Disneyland app to help you locate Donald Duck throughout the day.
Wishing Rosalie the most magical Disney getaway this summer!
Kristin