Historical clue formulations

• Sister-to-be, say — 2023-10-08
• Brother-to-be — 2018-12-28
• School recital — 2000-12-09
• Security — 2000-02-24
• Brother-to-be — 1999-01-15
• With 44- and 51-Across words by Francis Bellamy — 1995-07-02