  More than one Higgs boson may be present near the currently discovered Higgs
mass, which can not be properly resolved due to the limitations in the
intrinsic energy resolution at the Large Hadron Collider. We investigated the
scenarios where two $CP$-even Higgs bosons are degenerate in mass. To correctly
predict the Higgs signatures, quantum interference effects between the two
Higgs bosons must be taken into account, which, however, has been often
neglected in the literature. We carried out a global analysis including the
interference effects for a variety of Higgs searching channels at the Large
Hadron Collider, which suggests that the existence of two degenerate Higgs
bosons near 125 GeV is highly likely. Prospects of distinguishing the
degenerate Higgs case from the single Higgs case are discussed.
