  It is shown on the ground of a simple 6\times 6 neutrino mixing model that
one of three conventional sterile (righthanded) neutrinos, if light enough, may
be consistently used for explaining a {\it small} LSND effect. Then, it is
still considerably heavier than the three active (lefhanded) neutrinos, so that
a kind of {\it soft} seesaw mechanism can work. The usual condition that the
Majorana lefthanded component of the overall 6\times 6 neutrino mass matrix
ought to vanish, {\it implies} the smallness of active-neutrino masses versus
sterile-neutrino masses, when three mixing angles between both sorts of
neutrinos are small. In the presented model, the mass spectrum of active
neutrinos comes out roughly degenerate, lying in the range (5 - 7.5)\times
10^{-2} eV, {\it if} there is a {\it small} LSND effect with the amplitude of
the order 10^{-3} and with the mass-squared splitting \sim 1 eV^2.
