Post-it note with handwritten message in green marker. The message reads: "Hate is not welcome anywhere."

Handwritten note signed by Noah of Toronto. Written in black ink on the back of stationary with the logo of Marriott Hotels. Staining due to exposure to the elements at the Wilkins memorial.

Floral tag from floral arrangement sent by a group of six families. The tag commemorates the ten trees that were planted by the National Forest Foundation in memory of the October 27 attack victims. The note is printed on a tag with a beige background from a local florist.

Note from a member of The Church at Severn Run in Severn, Maryland. The note is enclosed in an envelope with church letterhead, reading: "The Church at Severn Run: Love Well, Live Jesus, Believe Big!" The note inside reads: "Love conquers all!! You are a child of God, therefore, you are loved. Continue to pray and worship. Please don't let hate win, love will overpower through all. Jenna [last name redacted]. YOU ARE LOVED!" The church's contact information is included on the back of the envelope.

Typed letter on Alfred University letterhead in hardback certificate holder, signed by Alfred University President Mark Zupan.

Post-it note with handwritten message in green marker. The message reads: "We will never forget. Love conquers Hate [heart]."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of a bird with a leaf in its mouth and floral and geometric motifs. The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Post-it note with handwritten message with blue marker. The message reads: "Stronger Than Hate!" Illustrated with a heart and signed: "TR."

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of a haloed dove flying in front of Noah's ark. The inside reads: "Dear Tree of Life members, I am keeping you and all of the others affected by this tragedy. My deepest sympathy, Molly [last name redacted] Holy Angels CCD."

Post-it note with handwritten message in black and red marker. The message reads: "Always in our heart."

Letter from a member of the Point Loma Community Presbyterian Church in San Diego, California. The letter reads: "To our esteemed sisters and brothers I offer sorrow in your losses, comfort to enter into your memories and many blessings for your bright future as a synagogue to overcome. With all my love- Russell [last name redacted]."

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of the words: "Don't Stop Believing." The back contains a handwritten note, as well as the stock signature: "From your friends at West Allegheny Middle School."

Note from a member of The Church at Severn Run in Severn, Maryland. The note is enclosed in an envelope with church letterhead, reading: "The Church at Severn Run: Love Well, Live Jesus, Believe Big!" The note inside contains prayers for peace and unity. The church's contact information is included on the back of the envelope.

Square card with white and yellow text against blue background. Card reads, "Mitzvah4Pittsburgh. Some spread darkness. We spread light. Choose a good deed. Choose a Mitzvah. Add light to the world," followed by four options and a place for respondents to list their name and email address. Some names and email addresses have been redacted for privacy.

Card from a student at West Allegheny Middle School in Imperial, Pa. The front features a hand-colored illustration of the words: "Be Strong" and other floral and geometric motifs. The back contains a handwritten note, as well as a sticker with the stock signature: "From your friends at West Allegheny Middle School."

Note from a member of The Church at Severn Run in Severn, Maryland. The note is enclosed in an envelope with church letterhead, reading: "The Church at Severn Run: Love Well, Live Jesus, Believe Big!" The note inside reads: "Just to let you know that you are truly in our thoughts and prayers. You are God's chosen people. He is always with you, and will never leave you. God Bless, Marce." The church's contact information is included on the back of the envelope.

Color photograph showing 13 people standing on either side of two Torah scrolls. Many of the men are wearing prayer shawls.

Square card with white and yellow text against blue background. Card reads, "Mitzvah4Pittsburgh. Some spread darkness. We spread light. Choose a good deed. Choose a Mitzvah. Add light to the world," followed by four options and a place for respondents to list their name and email address. Some names and email addresses have been redacted for privacy.

Card from a congregant at the Holy Angels Parish. The front cover contains a stock illustration of a haloed dove flying in front of Noah's ark. The inside reads: "I am sorry for your loss. From: Holy Angels CCD."