We report on a study of the finite-temperature chiral transition on an N-t = 4 lattice for 2 + 1 flavors of Kogut-Susskind quarks. We find the point of physical quark masses to lie in the region of crossover, in agreement with results of previous studies. Results of a detailed examination of the m(v,d) = m(s) case indicate vanishing of the screening mass of sigma meson at the end point of the first-order transition.