He began to form more cells. Jesus grew in just the same way as we all grew from day 1.
It is a week later and today could be called Holy Implantation Day.
Jesus implants, snuggling into the womb of His blessed mother. (And blessed is the fruit of thy womb, Jesus).
Without these hidden days we would not have had our Messiah and He could not have saved us.
Remember this when scientists and media pundits tell you it's just a few cells. It doesn't hurt to experiment and destroy them.
All those children are being murdered. Every child is a made in the image and likeness of God because He creates and we procreate. God came to us as fully human and fully divine and He grew as any man will grow from zygote onwards.