Want to Hack Someone's Android Phone ?

hello,i am from india,and i am in great trouble,pls help,it's about my sister.

from sources i got to know that,a guy trap my little sister(age:16) in fake love,and done inappropriate relation with her,i might think he has taken some bad photos of her,because when i check my sister's phone,i found an unknown SD card,which is not hers.their i found some proof of their relationship.but not all the evidence.And now he is highlighting her by discussing with his friends,i want all the proof to be sure about all these things,so i can produce these evidence infront of our family,to stop him,from further embarrassing our family,i got his only phone number.pls help,he is using an android phone,which i know.