How was the audio recorded? Three people, one microphone (on the camera/enternal, doesn't matter). The answer is not really.
Let me elaborate. There is no way to isolate individual voices with EQ - it is near impossible as human voices cover a rich range of sound frequencies.
You could keyframe volume adjustments, bring the volume up when the parents talk, bring the volume down when the baby is cooing.
If the baby has these spikes in volume from cooing or shrieking, you could use a compressor to squeeze those down and make them managable.
You might check out Sony SpectraLayers Pro for advanced audio surgery. I saw a demo clip and it seemed like magic