This time, they found it had spread to her liver, kidney, stomach and her brain.
"On February 27, 2017, K9 Officer Max Janofsky lost his amazing wife, Danielle, after her courageous battle with cancer, lasting only about three weeks," the department said on Facebook.
The couple already had a four-year-old daughter, Avery.
Danielle had a mole removed after doctors diagnosed it as melanoma nearly two years prior.
Her husband told NJ.com she always went to the doctor for check ups to keep an eye on it.
And despite the devastating diagnosis of metastasized melanoma, Danielle decided to deliver her baby boy, Jake on February 24, before she died.
Jake weighed one pound and 11 ounces when he was born via C-section.
Their newborn is currently receiving care at the University of Pennsylvania's Neonatal Intensive Care Unit.
Max, who is a retired Staff Sergeant, Bronze Star recipient, combat veteran who served several tours in Iraq and Afghanistan for the United States Army, their son, Jake, is currently on a ventilator with lungs that aren't developing.
He told NJ.com that his wife's hobby was "being a wife and a mother", adding that "it's what she loved to do".
He said Danielle had plans to take maternity leave this summer and relax on the beach.
A GoFundMe page was created to help ease the family's financial burden. More than $67,000 has been raised since it was created two weeks ago.
"Max was by her side every minute helping to ease her pain and remind her of how much love surrounds her and her family," according to the GoFundMe page.
The money the couple had went toward medical bills and because his wife was "so young" the family "didn't think we needed to have a major life insurance plan for her".
In addition to her medical bills, Danielle also had student loans to pay off.
"Danielle didn't have to work," he said. "She wanted to work and the money she got was put away for the kids' education."
She worked as a legal administrator for The Law Offices of William Staehle in Marlton.
The money raised on GoFundMe will be used to create trust funds for Avery and Jake.
The police department wrote that the "funds will be used to ensure the best medical care for Jake and additional funds will be used for education purposes for the children".