The measurement of distances to individual stars with Gaia is enabling the construction of deep colour-magnitude diagrams (CMD) for large volumes within our Galaxy in absolute magnitudes. Comparison with models (CMD-fitting) has allowed us to obtain the most detailed star formation history (SFH) of the bubble of 2 kpc around the Sun. Surprisingly, this SFH presents conspicuous star forming events around 5.7, 2 and 1 Gyr ago, coinciding with inferred pericentric passages of the Sagittarius dwarf galaxy (Sgr). We conclude that Sgr has been an important actor in the build-up of the stellar mass of the Milky Way disc.