YOU SAID:

I don't know why my brother is watching videos here when all he's doing is distracting me

INTO JAPANESE

兄が私の気をそらしているのに、なぜ私の兄がここでビデオを見ていいのか分からない

BACK INTO ENGLISH

I don't know why my brother should watch the video here when my brother is distracting me.

INTO JAPANESE

兄が私の気をそらしているとき、なぜ私の兄はここでビデオを見るべきなのか分かりません。

BACK INTO ENGLISH

When my brother distracts me, I don't know why my brother should watch the video here.

INTO JAPANESE

私の兄が私の気をそらすとき、私はなぜ私の兄がここでビデオを見るべきなのか分かりません。

BACK INTO ENGLISH

When my brother distracts me, I don't know why my brother should watch the video here.