A North Dakota mother has had a chance to hear her late son's heart beat inside a Nebraska transplant recipient.

Lisa Swanson cried as she heard the ultrasound of Terry Hooper's heart at Nebraska Medical Center in Omaha on Friday.

Hooper received the heart on Dec. 10, 2012, three days after 18-year-old Levi Schulz of Horace, North Dakota, died in a . Hooper had cardiomyopathy, which makes the heart lose its ability to pump blood effectively, and had been placed on the .

Hooper and Swanson have corresponded through letters since 2013, but Friday was their first face-to-face meeting. Schulz's twin brother, Shelby Schulz, also attended and listened to the ultrasound.

Swanson says she's sad her son isn't here, but also happy he was able to help Hooper.

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