  We use N-body cosmological simulations and empirical galaxy models to study
the merger history of dwarf-mass galaxies (with M_halo~10^10 M_Sun). Our input
galaxy models describe the stellar mass-halo mass relation, and the galaxy
occupation fraction. The number of major and minor mergers depends on the type
of dark matter; in particular, minor mergers are greatly suppressed in warm
dark matter models. In addition, the number of mergers that bring in stars is
strongly dependent on the galaxy occupation model. For example, minor mergers
are negligible for stellar halo growth in models with a high mass threshold for
galaxy formation (i.e. 10^9.3 M_Sun at z=0). Moreover, this threshold for
galaxy formation can also determine the relative difference (if any) between
the stellar haloes of satellite and field dwarfs. Using isolated simulations of
dwarf-dwarf mergers, we show that the relative frequency of major and minor
mergers predict very different stellar haloes: Typically, "intermediate" dark
matter merger ratios (~1:5) maximise the growth of distant stellar haloes. We
discuss the observability of dwarf stellar haloes and find that the surface
brightness of these features are incredibly faint. However, when several dwarfs
are stacked together models that form particularly rich stellar haloes could be
detectable. Finally, we show that stellar streams in the Galactic halo
overlapping in phase-space with known dwarf satellites are likely remnants of
their stripped stellar haloes. The mere existence of dwarf stellar haloes can
already put constraints on some small-scale models, and thus observational
probes should be a high priority.

Astrophysics of Galaxies