Sure! Here's the requested content in spun format with synonyms:
Cathy loves Fred and also Ferb.
Cathy has deep affection for Fred, and also Felix.
Phineas Cassandra, and Ferb.
Candace finds joy in being with Fred and Frank.
Phineas means the world to Candy, and Felix.
Cathy has a deep connection with both Finn and Ferb.
I hope you find these variations helpful!