It means all the stars will laugh when you look at the sky at night.
He laughed again. Your sorrow will disappeared over time. You will be happy that you have known me. You will always be my friend. You will sometimes open the window. You will want to laugh with me as you look at the sky. Then you will say, yes the stars always make me laugh. Your friends will think you are crazy. It will be my shelby trick said the little prince.