Personalized Disney Books-family members names instead of friends?

[csummerlin55]

I found a really good deal on personalized Disney Princess books (2 of the large ones for $13 including shipping) so I jumped on the deal. DD is 5 and really doesn't have any "best friends" she sees outside of the classroom. I don't really want to put the name of random girls that she may not really remember next year in the book. I was thinking of adding grandma, mommy and great grandma in for the "best friends" names. I also thought about putting her brother's names but I don't know if the princess books are made so that they would need to be girl names.
Has anyone ever had any experience with this or have any suggestions?