|The following is based on Fallout Shelter or Fallout Shelter Online and some details might contradict canon.|
The player's dwellers have caught wind of an abandoned pet in a nearby building, and can be sent out to rescue it. It is a very simple quest, enter the building and recover the dumped pet carrier, the only catch being the necessity of the participating dwellers being maximum level.
Minimum rewards; recovered the pet carrier:
Potentially scavengable rewards including, but not limited to: