Hi SereneNight - I have the Genesis baby and find, while it may not be perfect it is really very nice, a huge improvement over the Millenium Baby, and as mentioned, it can use Genesis clothing. I used cross dresser with the K4 license to transfer the Millenium baby’s original t-shirt and diaper to fit K4, and then used DS 4 autofit to fit it to Genesis.
The clothes that come free with Daz Studio 4 for the Genesis child has the t-shirt on the bottom right corner Genesis baby - and the diaper on the right side babies comes with the model. You can try autofitting any K4 clothing to the baby as well. The Genesis baby comes with several poses, and the skin texture in the picture. Since it’s Genesis, you could use any V4, M4, or K4 skin if you’d rather. I had success using Genesis emotions on it too. Please forgive my not so great picture, just wanted to put something together so you could see the difference between the Millbaby (top left corner) and the Genesis baby. Cathy