Wilmette crossing guard Herb Sheriff helps a Central School student cross at the corner of Wilmette and Forest avenues. Families marked Sheriff's 20th year with a surprise party. | Curtis Lehmkuhl~Sun-Times Media

Wilmette crossing guard Herb Sheriff has been escorting students safely across the intersection of Wilmette and Forest avenues for the past 20 years. Families noted the milestone with a surprise party.| Curtis Lehmkuhl~Sun-Times Media

Familes showed their appreciation June 6 for Herb Sheriff, the Wilmette crossing guard who has been stationed at Wilmette and Forest avenues for the past 20 years. | Curtis Lehmkuhl~Sun-Times Media.

Central School fourth grader Emma Chipman provides crossing guard Herb Sheriff with a cookie during a surprise celebration June 6 marking his 20 years at the corner of Wilmette and Forest avenues | Curtis Lehmkuhl~Sun-Times Media.

Wilmette crossing guard Herb Sheriff (right) talks with Central School fourth grader Will Kincaid during a celebration of Sheriff's 20th year at the corner of Wilmette and Forest avenues. Familes threw the partyJune 6 to show their appreciation.| Curtis L

Herb Sheriff talks with Highcrest Middle School sixth grader Samantha Chipman during a surprise celebration of Sheriff's 20th year at the corner of Wilmette and Forest avenues. | Curtis Lehmkuhl~Sun-Times Media