Hi all, hope someone can help me out!

I've been playing this family for a while and hate sims dying so at the moment i've got a family going on five or six generations. I know that sims only recognise relatives to three generations but I vaguely remember someone saying there was a mod or a hack that could fix that (or at least stop them being attracted to each other). Is there anything I can do to fix it? Right now one of my sims hasn't got a crush or anything but keeps wolf whistling his great aunt lol. Any way I can stop this?

I'm using all expansion packs except bon voyage and pets. Thanks!

There's a hack that fixes it here: http://faiuwle.wikidot.com/sims2hacks

Thank you!!