Metallicity of RGB stars of model sex156 a Sextans-type dSph with a perigalacticon and apogalacticon of 63 kpc and 150 kpc, respectively. As perigalacticon passages shut down the star formation within dSph (Sect. 3.2) models that have had multiple interactions will form fewer stars from Type Ia supernova enriched gas and subsequently contain fewer [α/Fe] poor stars at high [Fe/H]. Observationally, this an effect may be obscured if the gas in the dSph is poorly mixed, such as in the Carina dSph.