The photos drew the attention of two thieves, now suspected of breaking into the family's home while they were away.
It's an age-old crime, with new help from technology.
Goodyear Police worry this crime is an example that thieves are on the prowl, they're using social media to find their next victims.
Authorities say 19-year-old Damonte Rollings and Dwayne Gaither burglarized a home while the homeowner's were out of town.
"There was a stolen vehicle, keys to an additional vehicle, and cash taken," said Lisa Kutis with Goodyear Police.
But while the burglary itself may not be unusual, what is, is how police say the two allegedly plotted the crime.
Detectives say the suspects found their target through social media. One of the family members posted vacation photos to Instagram and the suspects were among the followers.
"The suspects were known to the family, had been to the families home, so they knew where they lived," said Kutis.
Goodyear Police say this time the burglary was reported within hours. The family's grandparents were watching the home while the others vacationed, and called police.
Police found the stolen car with one of the suspects allegedly inside. Now police use this as a social media warning.
"Please do not post your vacation plans on social media. Don't let people know what your itinerary is," she said.
Goodyear Police say when you are on vacation, cover your tracks online, and the old fashioned way at home as well.
"Make sure that you have a trusted person watching out for your home, stop the mail, things of that nature," said Kutis.