  We include the leading charge symmetry breaking contributions into the
hyperon-nucleon interactions derived within chiral effective field theory up to
next-to-leading order. Two low energy constants are determined using the
experimentally known differences of Lambda separation energies of 4-Lambda-He
and 4-Lambda-H. This allows one to predict the Lambda-neutron scattering
lengths for the first time based on data. Various sources of uncertainty are
discussed.
