Sure! Here's the requested content in spun format with synonyms:
Cassandra adores Finn and Ferb.
Candy Finn, and also Felix.
Philip Cathy, and also Foster.
Cassandra revels in being with Phineas and Foster.
Phineas means the world to Cathy, and also Foster.
Candace shares a bond with both Phineas and Ferb.
I hope you find these variations helpful!