YOU SAID:

I love to peak at my sister

INTO JAPANESE

私は私の妹でピークみたい

BACK INTO ENGLISH

I want to peak at my sister

INTO JAPANESE

ピークの妹にしたいのですが。

BACK INTO ENGLISH

I'd want to peak's sister.

INTO JAPANESE

ピークの妹をたいです。

BACK INTO ENGLISH

A sister peak to is.

INTO JAPANESE

妹にピークです。

BACK INTO ENGLISH

My sister is a peak.

INTO JAPANESE

私の妹は、ピークです。

BACK INTO ENGLISH

My sister is a peak.