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Cassandra Phineas and Foster.
Cathy has a soft spot for Phineas, and also Foster.
Phineas holds a special place in the heart of Cara, and Ferb.
Cathy takes delight in being with Phineas and Ferb.
Fred has a special place in the heart of Cassandra, and also Foster.
Cathy shares a bond with both Finn and Felix.
I hope you find these variations helpful!