Can two parents that are Type have a child that is Type B

Day 4-5

Explanation:

The first cell differentiation occurs when the embryo reaches approximately five days after fertilization, forming the blastocyst.

In this case, the cells on the outside undergo the process of differentiation and become responsible for the formation of embryonic attachments (structures that derive from the embryo's germ leaflets but are not part of the embryo's body, such as the amnion).

In the meantime, those cells that remained inside, also undergoing the process of differentiation, become pluripotent stem cells, which are responsible and capable of forming all tissues.

Previously, when they are still undergoing the process of dividing up to 8 cells, each cell is capable of forming a complete being when inserted into an egg.

By going through the whole process and becoming pluripotent stem cells, they can form all kinds of body tissues, but no longer a complete being.