Scaling relations between the mass of stellar halos and that of the associated central galaxy (left panel) and intracluster light (right panel). The color bar encodes the dark matter halo concentration, with redder colors corresponding to higher concentrations. The stellar halo mass correlates well with the BCG and the ICL mass, with a notably smaller scatter in the ICL case. In both relations, halo concentration plays a key role: stellar halos tend to be more massive in less concentrated dark matter halos, which are also the most massive systems.