  At the Large Hadron Collider, we prove the feasibility to detect pair
production of the lightest CP-even Higgs boson $h$ of Type II 2-Higgs Doublet
Models through $q q^{(')}\to q q^{(')} {hh}$ (vector-boson fusion). We also
show that, through the $hh\to 4b$ decay channel in presence of heavy-flavour
tagging, further exploiting forward/backward jet sampling, one has direct
access to the $\lambda_{Hhh}$ triple Higgs coupling -- which constrains the
form of the Higgs potential.
