I love this topic. lol...
I love approaching groups, because its fun. But regarding the mother and father thing, you need totally different approaches.
Lets address the issue with Groups of girl friends first, because that is the easiest.
With groups, Chase have already touched upon this topic in his blogs.
Its about finding out who the "Leader" of the pack is.
You must always give at least 30% of your attention back to the leader, and 70% on the girl you are interested in.
You must make the leader like you, or she will be your cock blocker. If the leader finds you cool, and likes you too.. then she will more likely to encourage her girl friend that "you are a great catch". If you choose to ignore the leader, she will show you who is boss.
So your job is to put on your "Challenge Accepted!" mode, and jump right into the group with lots of enthusiasm, ask an INTERESTING question, and try your best to find out who that leader is. It usually is the one who voices her mind out the most and more dominant.
Now with the Mother / Sister issue, this is easy. It is already clear that the Mother is obviously the leader. You simply apply the same principle. If its the sister, you just have to find out who is older. However, here you need to give the mother a bit more attention, but state clearly that you are interested in her daughter. If she likes you, she may just give you her blessing and allow you a couple of minutes to talk to her daughter. I repeat..
your intention must be clear.
Parents love honest lads, and hate sleezy guys! It shows that you are honest yet bold.
Regarding the Father however, this is slightly difficult. He is clearly the authority. He is more like a ready made obstacle ready to smash you down.
There is only one way to go about this. -
Show Respect and Honesty.
You MUST NOT ignore him. You must open HIM, not her. you must give absolute 100% attention to him. Think of yourself in his shoe. How can a guy get pass you for your daughter?
Well, if he came up to you and immediately show humbleness and respect towards you, then ASK for PERMISSION... you would probably think about it right?
I have done this a few times, and it goes something like this:
"Excuse me Sir, I don't mean to trouble you or be rude, but I just couldn't help but notice how attractive your daughter is,
*turn to look at her briefly, and turn back to him* and with your permission, I was wondering if you're not in a rush, would be ok for me to speak to her for a couple of minutes?" - While looking at him in the eyes and with a WARM SMILE. In fact, you should have been holding on to that warm smile of yours from the moment you approached.
Usually the father would say its ok (surprise surprise!) Theses are the couple of responses I got if I remembered them correctly:
- "Sure lol" (At a wedding guest table, this especially works in a lively environment)
- "Umm.. *looked at her* (She ended up talking to me instead, she happened to be the leader

- *Looked at me firmly* "You have 5 minutes.." (This one was scary, but I said thanks, and did my usual opener. I didn't get far on this one, but hey I tried!)
- (This one is hilarious, I'll always remember it.) "You think SHE is attractive???!" - immediately she yelled "DAD!!" (LOL)
So there you go, it can be done, and in fact, easily. Just remember to state your intention clear at the beginning with the parents, and give attention to the leader of girl groups as well.
Happy Hunting.