A 7-year-old Wisconsin girl fighting an inoperable, incurable brain tumor is being flooded with letters of comfort -- from dogs.

Emma Mertens is fighting DIPG, according to a GoFundMe set up on her behalf. St. Jude's Children's Research Hospital says DIPG (Diffuse Intrinsic Pontine Glioma) starts in the brain stem. The survival rate is very low.

The GoFundMe had an initial goal of $50,000 to help with medical and other expenses but had reached more than $81,000 as of Wednesday morning, just over a month after it was launched.

In addition, the family is asking people to mail or email letters from their dogs to Emma, along with photos or videos. People are also posting them on Emma's GoFundMe page.

The family is also using the CaringBridge website for updates on Emma's fight. They said both the email box and their post office box were completely full of letters Tuesday.

"Many pictures of puppies really made her laugh or smile. Thank you to everyone who is trying to put a smile on her face, we appreciate the gesture," wrote Geoff Mertens.

If you want to send Emma a letter through regular mail, the address is:

Emma Mertens

PO Box 230

Hartland, WI 53029

The email address is emmalovesdogs7@gmail.com