Have you tried not talking about it but put them in situations together? Maybe you need to take your son somewhere and now somthing has come up for her, could he please take her? It won't happen overnight. I don't think you should try to force the relationship but try to help it along as quietly and as gently as you can.
kat
Corey, I love this! Schedule something when you know he won't be with the baby or when he should be available, and then say he needs to take her b/c you need to X or Y. Worth a shot anyway. Maybe your D8 could thank him afterword or tell him how she likes to spend time with him or enjoyed herself whatever. Cause I'm thinking maybe positive reinforcement would do better for him than the negative--which doesn't seem to work at all?