Complex sentence: In 2004, he and his real life younger sister Abigail Breslin played on-screen siblings in "Raising Helen" and in "Princess Diaries 2", in which Spencer played a prince and Abigail made a cameo as a girl at an orphanage.
Split into simpler sentences: In 2004, he and his real life younger sister Abigail Breslin played on-screen siblings in "Raising Helen". They once again starred together in 2004's "Princess Diaries 2", in which Spencer played a prince and Abigail made a cameo as a girl at an orphanage.