Almagro took part in the various expeditions that took place in the Gulf of Panama, including those of Espinosa, which were supported by Balboa's ships. Almagro was recorded as a witness on the lists of natives whom Espinosa ordered to be carried. He remained as an early settler in the newly founded city of Panama, staying there for four years, managing his properties and those of Pizarro. He took Ana Martínez, an indigenous woman, as a common-law wife. In this period, his first son, "El Mozo", was born to them.