Gero was born in Fier, central Albania, in 1926. At a very young age she was involved with the resistance, as part of the communist cells opposing the Fascist occupation. Her home was one of the "safe houses" used by the resistance members for their activities. On 14 September 1943, Gero and other 67 girls from Fier, 68 in total joined the same night the ranks of the partisans of the National Liberation Movement, a remarkable moment in the history of Albanian resistance, considering the fact that Fier had around 5,000 people at the time.