This can be because of their genetics. The siblings may not have inherited their parents looks, but maybe they inherited their grandparents looks, or even their aunts looks. This is all due to genetics. It's sort of the same thing, when two caucasian parents have an african-american child. That would be because somewhere along the family tree someone was african-american.
Anyways, I hope this helps!
Answer:
A normal type of white blood cell that has coarse granules within its cytoplasm.
The endoplasmic reticulum aids in the production and movement of proteins and other materials through the cell.
