The orientation and size of fractures created during hydraulic stimulation is governed by the in-situ stress state. Reservoir production changes both the magnitude and the direction of the principal stresses, and these stress changes can be calculated using a geomechanical model. In this study, we employ a 4D geomechanical model calibrated with time-lapse seismic time shift data to understand the direction of fracture growth during hydraulic stimulation of a horizontal injector well. The horizontal well was drilled in the (expected) direction of the maximum horizontal stress, such that the strike direction of the fractures is aligned with the wellbore axis. Our study shows that production from a nearby well has rotated the directions of horizontal stresses, and some of the hydraulic fractures now grow perpendicular to the wellbore axis. The stress-field calculations and predicted directions of hydraulic fractures are substantiated by the observed time-lapse seismic amplitude signal. This signal shows increased fluid flow in the predicted fracture direction for individual stimulated zones.