Overall I think your friend has a nice start! I would love to hear more!
Here are some suggestions to making it better:
The people of the busy castle market fled to the quite village of
Kakariko.
I think your friend meant "quiet"
to let other races know that he was not to be messed with.
Maybe the word "reckoned" would make him seem more powerful?
This section here is a little awkward in the way it is structured. I wasn't really sure what your friend was trying to say:
Hyrule remained at
peace as
the two because four the twin boys, _____ and ______. The boys were
two
when the family welcomed one more, a baby girl named _____.
One last thing is that in the Prelude your friend didn't really talk about how Link got out of the Sacred Realm. Your friend went from this:
Link
was
sealed in the Sacred Realm for seven years.
to this:
At each temple, Link put an end to Ganondorf’s evil...