公園に遊べるために息子と一緒に公園に行った
I went to the park with my son for him

to play.

でも、息子は車を乗ってる間に寝ちゃった
However, while riding in the car he fell asleep

影の中に公園の駐車場で息子が起きることを待ってる
Now I’m in the shade in the parking lot waiting for him to wake up.