YOU SAID:
she held the lantern as she watched her father practice
INTO JAPANESE
彼女は父親の練習を見ながらランタンを握った
BACK INTO ENGLISH
She held the lantern while watching her father's practice
INTO JAPANESE
彼女は父の練習を見ながらランタンを握った
BACK INTO ENGLISH
She held the lantern while watching her father's practice
That didn't even make that much sense in English.