what does baby call you?

Happy Baby is almost 8 months old and he calls everyone DADA. We have been trying to get him to say MAMA because that seems like the natural progression of learning to talk for vast majority of babies. I belive I will legally be his MAMA one day and since he hasn't seen his biomom since he was 3 months old I really don't feel bad about it. I believe every baby needs a MAMA.