Siobhan Tilly
- Full Name: Siobhan Tilly
- Species: Human
- Gender: Female
- Mother: Adèle Tilly
- Husband: Iain Tilly ( - 2232 - )
- Marriage ended by 2248 (DIS Novel: The Way to the Stars)
- Daughter: Sylvia Tilly
- One older daughter with a different father (DIS Novel: The Way to the Stars)
- By 2248: Elected Federation Councillor for United Earth (DIS Novel: The Way to the Stars)
- By position on the Federation Security Council