This is the first reference to illness in Scripture. We are not told how much time passed, but it was years. The individual blessings of Israel on his children and the two children of Joseph have significance for the historical development and have prophetic implications also.
Keep in mind that these dreams that helped shape the events in Joseph’s life always occurred in twos. The dreams established matters and according to Torah, that must be done with two or more witnesses. The misfortunes of Joseph began and ended with these dreams.