grammar glitch in Lincoln's grave marker

My sister Gly visited recently the famous Lincoln Tomb in Springfield, Illinois. One of the photos she posted on FB was a marker whose inscription really bothered me.



Then on 3 July, I finally wrote an email to the Illinois Historic Preservation Agency to raise the matter. Below is the email.

*****

Sir/Madam:

I'm from the Philippines and I have a friend who is still in the US touring historical sites. She had gone to many wonderful places including the Lincoln Tomb. As proof, she had posted photos on Facebook. And this marker (please see attached photo) with the following inscription really bothers me, thus:

THE GRAVE OF ABRAHAM LINCOLN

This structure marks the graves of Abraham Lincoln, his wife Mary, and three of their four children. Members of the Lincoln family chose the site in May 1865. Planned and built the years following the president’s shocking death, the tomb remains an imposing symbol of the peoples’s (underscoring mine) sorrow.

Doesn't the "s" after the apostrophe make the sentence ungrammatical? If not, please enlighten me. Thank you very much.

*******

Then on 9 July, I received a reply from the Illinois Historic Preservation Agency, saying it acknowledges the error and promising to correct it as soon as possible.

.

The full text of the email runs, thus:

Romel,

Thank you for pointing out this error. We do appreciate it. One can never have enough eyes for proof reading. We will take steps to correct it as soon as possible.

Best,


Karen E. Everingham
Historic Sites Division
Illinois Historic Preservation Agency
217/785-1584
F: 217/785-8117
www.illinoishistory.gov/hs/sites.htm
www.illinoiscivilwar150.org