Why did Moshe send Tzipora and his children back to Yitro in the desert? Why did they come back to Moshe later? Why is Yitro’s name changed from Re'uel?

1. Rashi (Shemot 18; 2)comments that Moshe was coming down to Egypt with his wife and sons thus when Aharon saw them he suggested his brother to send them back for there's enough suffering in Egypt and no need to ad more people to that. 2. When they heard about the miracles exodus – they decided to rejoin Bnei Yisrael. (Ramban ibid) 3. The Midrash (Raba Shmot 1; 32) notes that Reuel is Yitro and his name was change since Re'a means Friend and El is G-d, he became a friend to G-d. Rashi (Shmot 18;1) however bring an opinion that he is the father of Yitro.