Aftershocks

wikipedia: “An aftershock is a smaller earthquake that occurs after a previous large earthquake, in the same area of the main shock.  Aftershocks are formed as the crust around the displaced fault plane adjusts to the effects of the main shock.”

Our house shaked just now. It was the aftershock of the earthquake that happened 6 weeks ago. It is a usual thing which occurs after a big earthquake, and it can last for months. It was not serious though, not a big one, with the biggest maybe magnitude 3 like that, but mostly are minor ones(magnitude 1~2). It is becoming a common thing since it is happening everyday here, a few times each day. But one thing that`s making me curious is the time when it happened in the early morning, like the one just now. It would happen at almost exactly the same time every morning, around 4am, after Subuh prayer. Do aftershocks have cycles? Is it a normal thing? I wonder.