Why didn’t I process that I had been sexually assaulted?

When I was in the 4th grade I was sexually assaulted by my best friends uncle. When I was in 6th I was sexually assaulted and nearly raped.

The one in 6th grade traumatized me because the sexual assault went on for weeks but I just realized that I never really reacted to what happened in the 4th. Why? I was terrified about what happened in the 6th but after what happened in the 4th grade (although still terrified in the moment) I never thought about it afterwards.