Any last name that you like is a good one! Your characters are yours - you don't have to ask some anonymous person on the internet about them.
Here's a good LINK to a list of last names you might like.
Cassidy can be both a first name and a last name. It is more commonly used as a surname, but it can also be given as a first name.
Cassidy is a great name for a baby girl. Cassidy means beautiful in the greek gods name. In other places it means wise and clever.
Cassidy Higgins, from masterchef Australia.
yes it is a good name not alot of kids have it
Cassidy Alexander's birth name is Cassidy Joyelle Alexander.
Cassidy Gard's birth name is Cassidy Rainforest Gard.
Martin Cassidy's birth name is Martin Joseph Cassidy.
Natalie Cassidy's birth name is Natalie Ann Cassidy.
Shaun Cassidy's birth name is Cassidy, Shaun Paul.
Ted Cassidy's birth name is Theodore Crawford Cassidy.
Cassidy Spring's birth name is Wildermuth, Cassidy Spring.
Sheelah Cassidy's birth name is Sheelah Beth Cassidy.