  We consider MSSM with right-chiral neutrino superfields with Majorana masses,
where the lightest right-handed sneutrino dominated scalars constitutes
non-thermal dark matter (DM). The $\Delta\,L=2$ masses are subject to severe
constraints coming from freeze-in relic density of such DM candidates as well
as from sterile neutrino $\textit{freeze-in}$. In addition, big-bang
Nucleosynthesis and $\textit{freeze-out}$ of the next-to-lightest superparticle
shrink the viable parameter space of such a scenario. We examine various
$\Delta\,L=2$ mass terms for families other than that $\Delta\,L=2$ masses are
difficult to reconcile with a right-sneutrino DM, unless there is either (a) a
hierarchy of about 3 orders of magnitudes among various supersymmetry-breaking
mass parameters, or, (b) strong cancellation between the higgsino mass and the
trilinear supersymmetry breaking mass parameter for sneutrinos.
