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Type Ia supernovae (SNe Ia) have a low intrinsic magnitude dispersion comma therefore are highly standardisable and make excellent cosmological distance indicators. After correcting for light-curve properties comma such as width (stretch) and intrinsic colour comma this dispersion is further reduced. However comma an intriguing dependence on SN host galaxy properties remainsdoublePoint SNe Ia associated with high mass hosts are brighter than those in low mass hosts. If the remaining brightness dispersion is entirely due to global host galaxy properties comma SNe Ia associated with the same galaxy (siblings) should be cosmologically similar comma with comparable intrinsic colours comma stretches and Hubble residuals. However comma prior studies have shown that this is not the case comma and they are as different as any other pair of SN. With the high quality images we will obtain with this proposal comma we will investigate the local environments of a sample of low redshift (low-z) siblings comma by measuring rest-frame U-R photometry within small apertures around each SN comma to see if sub-galactic differences in environmental properties are the answer to improving SNe Ia standardisation. Prior sibling analyses have typically been limited to the duration of individual surveys comma meaning that their sibling samples have primarily been found in high mass comma elliptical galaxies comma which are associated with higher rates of SNe Ia. Our proposed sample of archival low-z siblings differ in explosion times by an average of 14 years allowing for an increased understanding of the rates of sibling SNe Ia comma detailed investigation of a diverse variety of host galaxy morphologies comma and thus a diverse range of local environments within those galaxies.