<p>Intraspecific interactions among sibling insects may manifest as either aggressive or cooperative behaviours, shaped by environmental conditions, such as starvation, genetic relatedness, and population density. This study examined the effects of starvation duration and larval densities on different larval instars of the sub-social tortoise beetle, <i>Aspidomorpha miliaris</i> Fabricius. We hypothesized that fifth instar larvae would undergo premature pupation, regardless of starvation duration and that grouped larvae would exhibit higher starvation tolerance than solitary individuals. Larvae at the onset of each instar were reared under two density conditions: solitary (one larva) and grouped (three larvae) and subjected to starvation treatments of 12h and 24h. After starvation, an optimal food supply was provided until adult emergence. Results indicated significant effects of both independent factors and their interactions on larval survival, although pupal survival remained largely unaffected. Notably, second instar larvae exhibited supernumerary moulting as an adaptive response to starvation, while this phenomenon in third instars occurred only under grouped conditions. The study thus, concluded that larvae of <i>A. miliaris</i> thrives better in groups and can undergo supernumerary moulting under nutritional stress conditions.</p>