Six-year-old Hattie Yvonne Jackson vanished from Rock Creek Park in Washington, D.C., on July 21, 1961. That afternoon she was playing and swimming with her older brother and friends when a police officer warned them the creek was polluted. After the officer left, a man sitting nearby offered to drive the children to a cleaner swimming spot; the children declined and continued to play. Shortly afterward Hattie disappeared without anyone noticing her leave.

Witnesses later said two young men were seen helping a girl matching Hattie’s description into a dull blue/gray older-model Chrysler, possibly a Plymouth, with yellow license plates near the park.

Investigators followed leads over the years: a tip about a man on bond days after the disappearance; a 33-year-old musician who confessed in September 1961 but later admitted lying; and Thomas Welton Holland, who resembled the sketch and had a criminal history, though no direct evidence tied him to Hattie. An FBI inquiry compared the case to the unidentified child in the 1962 Philadelphia box case, but autopsy results excluded Hattie. Hattie remains listed as a missing person. If anyone has memories of Rock Creek Park in July 1961 or information about the men or car seen that day, please come forward.