I've done it, though never with both parents present just the mother. I'd probably consider it nearly impossible with Dad around, and with her Mother it's an extremely tricky maneuver.
The key is to be charming and interesting, well dressed and looking good but scale back the sexual vibe, but at the same time comfortable with who you are and unashamed of what you're doing; balls.
Also, think of a girl and her mommie as a set; engage the mother just as frequently as you do the daughter. If you're efficient and the stars are all aligned, the mother will practically order her daughter to give you her phone number.
The key is to be charming and interesting, well dressed and looking good but scale back the sexual vibe, but at the same time comfortable with who you are and unashamed of what you're doing; balls.
Also, think of a girl and her mommie as a set; engage the mother just as frequently as you do the daughter. If you're efficient and the stars are all aligned, the mother will practically order her daughter to give you her phone number.