BOSTON (CBS) — One of the thousands of heartfelt mementos left in Copley Square was a stuffed animal teddy bear from two young sisters.

At the time, they didn’t even know Martin Richard’s name, they just knew he was taken too soon.

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WBZ NewsRadio 1030’s Carl Stevens reports

“The note says ‘Dear little boy I am so sorry you are in heaven, my sister and I want to give you a gift to show how sorry we are, from Isabella and Ava,”said City Archivist Martha Crilley.

Crilley found many more touching items, like a note from a family who lost a loved one on September 11, to the Boston Marathon families.

It says, ‘We feel your pain, we understand, God bless you all.’

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“People really poured their hearts out in a lot of theses pieces that they left,” Crilley said.

Many of those pieces will be on display at the new exhibit including the one thing people left behind the most – sneakers. Hundreds of pairs, many from runners who were not able to finish the race because of the tragedy, but have vowed to be back.

The exhibit opens Monday and runs through May 11 at Boston Public Library.

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