We present detailed characterization of laser-driven fusion and neutron production (∼ 10 5 /second) using 8 mJ, 40 fs laser pulses on a thin (<1 µm) D 2 O liquid sheet employing a measurement suite. At relativistic intensity (∼ 5 × 10 18 W/cm 2 ) and high repetition rate (1 kHz), the system produces deuterium-deuterium (D-D) fusion, allowing for consistent neutron generation. Evidence of D-D fusion neutron production is verified by a measurement suite with three independent detection systems: an EJ-309 organic scintillator with pulse-shape discrimination, a 3 He proportional counter and a set of 36 bubble detectors. Time-of-flight analysis of the scintillator data shows the energy of the produced neutrons to be consistent with 2.45 MeV. Particle-in-cell simulations using the WarpX code support significant neutron production from D-D fusion events in the laser-target interaction region. This high-repetition-rate laser-driven neutron source could provide a low-cost, on-demand test bed for radiation hardening and imaging applications.