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The Case of the Unsent Invitation: The Anna & Ava Detective Agency, Book 9
Paperback
Series: The Anna & Ava Detective Agency, Book 9
Chapter BooksFamilyGeneral Juvenile Fiction
Publisher: Independently Published
Published: Feb 16 2026
Pages: 92
Weight: 0.26
Height: 0.22 Width: 5.50 Depth: 8.50
Language: English
When a birthday invitation doesn't arrive, the damage begins long before the party.
Emma is known for being organized, thoughtful, and reliable. So when Lily doesn't receive an invitation to Emma's exclusive bowling party, the class is quick to defend Emma's reputation.
But Lily is certain.
She didn't get one.
Now Anna and Ava must investigate something more delicate than a missing object. This time, the mystery isn't about what was written - it's about what was delivered.
As assumptions spread and feelings quietly grow, the sisters follow the evidence step by step:
- Was the invitation dropped?
- Picked up?
- Lost in a backpack?
- Or never delivered at all?
What they discover is more surprising than anyone expected - and more important.
Because sometimes the difference between intention and impact is only a small interruption...
but that small gap can create very big feelings.
The Case of the Unsent Invitation is a thoughtful, age-appropriate mystery about:
- Reputation and confirmation bias
- Ownership and apology
- How misunderstandings grow
- Why delivery matters as much as intent
Perfect for readers ages 7-12 who enjoy real-world school mysteries grounded in empathy, logic, and teamwork.
The Anna & Ava Detective Agency returns with a case that proves:
Proof solves paper.
Ownership solves people.
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