So Aaron met Moses on the mountain of God and kissed him.
28 Moses taught Aaron all of the signs that God taught him.
29 Moses and Aaron met with the Hebrew elders and showed them all of God's magic tricks. 31 And the people believed.
A few more words about this episode
His wife and sons (4:20)
Up to now, Moses only had one son, Gershom, who was born in verse Exodus 2:22. Only one other son is mentioned in the Bible, Eliezar (1 Chronicles 23:15).
The story doesn't say for sure, but apparently God's motive for trying to kill Moses was that his son (Gershom, or one of the other nameless ones) wasn't yet circumcised.