  In the NMSSM it is well possible to find an additional Higgs boson with a
mass below 125 GeV which remains invisible in standard Higgs boson search
channels. We study the Higgs pair production cross sections times branching
fractions in this scenario, focusing on gluon fusion and the bb+tautau and
bb+gammagamma final states. Summing over the SM-like and the lighter Higgs
states, the production cross sections times branching fractions are never below
the ones for SM Higgs pair production. Sizable enhancements of the signal rates
are also possible, notably if a lighter Higgs state is produced. However, the
rates involving at least one lighter Higgs boson are not always sufficiently
large to guarantee its discovery.
