Penpal

My cousin Joshua (7 y/o) has written me 3 letters. This is 1 of them. He is suppose to write to penpals as instructed by his school. My aunt decided to cheat abit by asking me to be his penpal. Its quite wierd. His letters have no questions for me to answer, just what he has done, kind of like a diary. So how am I suppose to reply? And am I suppose to reply like a 7 y/o or a young adult? No Eye Deer.