Master F. G. Wagner lived in Williamsport, the principal city in Lycoming County of north-central Pennsylvania and once a very prosperous center of trade and commerce.

https://en.wikipedia.org/wiki/Williamsport,_Pennsylvania

Located on a branch of the Susquehanna River, Williamsport was connected to the Pennsylvania Canal system and supported a lumber industry and, later, foundries.

The city was somewhat larger in 1910 than it is today.

https://www.britannica.com/place/Susquehanna-River

The postcard address does not include an “In care of” – which might identify the household in which the boy lived.

In August of 1911, Master Wagner received a cute postcard from Philadelphia.

The sender’s name is rendered within quote marks as though it were a child’s mispronunciation.

I decipher “Tate”, but that may be part of a juvenile attempt at saying the name.

The face of the postcard is a cute drawing of a sad-faced dog attending intently to a tearful boy.

The remarkable ability of a dog to respond to human emotions is wonderfully portrayed by the artist.

The artwork was copyright in 1911 by T. P. & Company of New York.

I believe that the artist is Bernardt Wall, an artist and historian who also illustrated more than 5000 postcards.

https://en.wikipedia.org/wiki/Bernhardt_Wall

Beneath the boy and his comforter is the printed title, “Cheer Up, Old Boy”.

Despite the sadness of the pictured boy, I suspect that the postcard was marketed as a humorous or comic piece of work.

For that reason, I don’t assume that the recipient had experienced some painful loss.

Young Master Wagner preserved the postcard in very good condition throughout his life.

One hopes that he enjoyed the companionship of a pet, and that he maintained a long relationship with his correspondent from Philadelphia.