Like would him being a nice guy even matter as long as he has a great body

I have an Australian friend who is dealing with a very messed up situation with an older man from New Zealand who is actively trying to seduce his 16 year old sister. My friend and her sister live in NSW and the age of consent is 16. My friend has told me that her sister is very naive and gullible as well as attention seeking so she keeps entertaining the older man. The older man has flirted with her and skype called her through video multiple times and does not stop. Apparently the older man wants to come meet my friend's sister in person in Australia. In my friend's situation, what can he possible do to protect his sister from this creepy older man legally?

So I know in the past when you have someone blocked it deleted their comments. Recently, I'm having a disagreement with my SO that when blocking someone on IG today, their comments are deleted from more modern picture (last 3 years) however on pictures from 4+ years ago, the comments do not disappear. Can someone back me up, maybe test it out and let me know. I've experimented and it checks out but of course that evidence is not good enough. Thank you in advance.

Im a 17yr girl& i have trouble being honest.I took my brothers KIA& hit a car making a right turn.The guy ONLY took the license plate.I lied about hitting the car in fear of getting in trouble.2 weeks later i crashed my other brothers car really bad and told him.3 weeks later my brother the one with the KIA got a letter from insurance company saying he was involved in a collision accident. I was going thru a breakup& had just crashed the other car, not getting enough sleep or eating& well I didnt have the guts to be honest and face the conséquences so i hid it.He recieved another letter for reimburstment owing 2000. I had to tell him the truth&He might get his license taken away and Everything is my fault and I just need someone to talk to and help me fix this myself. What should i do?!

So my husband and I got married a year ago and ever sense his mother has talked smack about me for stealing her son, and told her son he was never going to amount to anything FOR THE FIRST ENTIRE 6 MONTHS OF OUR MARRIAGE. I'm talking on a daily basis bashing us both. And yet my husband was still going there whenever she needed help cleaning and such, because if you don't do what she says she gets even meaner. For example on our first year anniversary she called and yelled at my husband saying he has no idea how he hurt her, (for staying away from her since she treats us so mean). So we cut her off and haven't seen her for months, and now she calls my husband and asks him to help her move, ON MY BIRTHDAY WEEKEND, and my husband told me and got angry at me for being mad, because he seems to want to bend over backwards for this evil woman. This is just a big mess, what should I do? Thanks.