You may be looking for Gavin (Twin Piques).

King Gavin was a monarch on an Earth-like planet. He had two daughters, Japonica and Corianda.

The Second Doctor and Jamie McCrimmon helped him stop his brother Conrad from usurping the throne. After celebrating their victory, the Doctor and Jamie departed, only to arrive on an identical planet ten years later in which their future selves (or their doubles) had helped King Conrad defeat his brother Gavin. After some initial confusion, the Doctor worked out what was going on and used the TARDIS' fast return switch to bring together King Conrad and King Gavin to learn why the brothers turned out differently.

Gavin and Conrad argued with each other until they tired of it, and the Doctor returned them to their respective planets. (PROSE: Twin Piques)

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