The spin Seebeck effect generates spin currents in various materials when they are subjected to a temperature gradient. These spin currents persist over length scales many orders of magnitude greater than the spin diffusion length and thus may hold the key to realising spintronics devices.We wish to continue a neutron reflectivity investigation into the archetypal spin Seebeck system, thin film yttrium iron garnet (YIG) on a substrate of gadolinium gallium garnet (GGG). It is known that when a thermal gradient is applied that a magnetisation gradient is produced, however this magnetic redistribution has never been directly observed. We aim to do just that, giving new insight into the effect, as well as to answer the questions our previous investigations posed.