Complex sentence: His siblings included John Miller Andrews, Ulster Unionist Party member and County Grand Master of the Orange Institution in County Down and went on to become Prime Minister of Northern Ireland, and Sir James Andrews, the future Lord Chief Justice of Northern Ireland.
Split into simpler sentences: His siblings included John Miller Andrews, Ulster Unionist Party member. He was County Grand Master of the Orange Institution in County Down and went on to become Prime Minister of Northern Ireland, and Sir James Andrews, the future Lord Chief Justice of Northern Ireland.