A three-body calculation for the and hypernuclei has been undertaken. The respective cores are . The interactions in the system, modeled as , are reasonably well known. For example, the p n interaction is well determined by the p n scattering data, the -p interaction can be fitted to the binding energy. The -n interaction can be fitted to alpha-n scattering data. For the He-4-n system the s-wave can be modeled alternatively as a repulsive potential or as an attractive potential with a forbidden bound state. We explore these alternatives in He-6, because the interaction comes into play in modeling as well as in our + n + n model of , where the valence neutrons are Pauli blocked from the s-shell of the core nucleus.