  A tree-level flavor changing neutral current in the up-like quark sector
appears in one of the variations of the Littlest Higgs model. We investigate
the effects of this coupling in the D+ -> pi+ l+ l- and D0 -> rho0 l+ l-
decays, which are the most appropriate candidates for the experimental studies.
However, the effects are found to be too small to be observed in the current
and the foreseen experimental facilities. These decays are still dominated by
the standard model long-distance contributions, which are reevaluated based on
the new experimental input.
