Now that Joseph has been reunited with his brothers, he can not wait to see his father as well. Besides the fact that his father is elderly, there are still five more years of famine to go, and if the family were to remain in Canaan, they would become destitute as supplies became scarcer and harder to obtain.
Apparently the brothers are still staring at him, unable to believe that it is really him. Or, if it is him, they don't understand why he is not furious and demanding revenge. For Joseph has to say the following:
" 'You can see for yourselves,
accorded to me in Egypt
Then he threw his arms around his brother Benjamin and wept, and Benjamin embraced him, weeping. And he kissed all his brothers and wept over them. Afterwards his brothers talked with him."
(Genesis 45:12-15 NIV)
Finally, the news seems to sink in to the brothers' minds. There is plenty of embracing and weeping to go around and then they probably stayed up half the night catching up on the past 20-plus years that they have been apart.