A baby in a dream doesn't necessarily mean a baby. A baby in a dream generally represents feelings such as possessiveness, insecurity, joy, curiosity, vulnerability, lack of responsibility, a need for love, intense dependence, innocence, and are symbols of the purest form of a human whose possibilities are endless. Also represents a new phase of life.
At times of great change and renewal, a baby may appear in a dream and represent your potential and a new beginning.

Have you started any new projects?
Have either of you been feeling vulnerable, or insecure lately?
Have you felt as though one or the other has been acting childish lately?

Hope this gives some insight, best wishes!