How can I tell If my sisters friend likes me?

[Anonymous]

She and another one of my sis old friends came over for new years last night and I joined them. We all got really really drunk but this girl and I would always look at each other and smiling (the really warm kind of smile). My question is, even though there is that brother/sisters friend scenario in the play, how can I know that she likes me? We had a brief chat while my sis was making breakfast and we seemed to get along. Also at one point I checked her out while she was stretching in front of me and she saw me and just kept stretching and smiling at me. (Im 100% sure she knew I was looking up and down from head to toe). Thoughts? And does anyone know of any experiences? The fact the she's my sis friend is holding me back

[Chadster]

the fact she's your sis's friend is a bonus, ask her out or see if she wants to just go for a walk... put your hand close to hers and if you end up holding hands.. she's yours!

[KailahBooBoo]

Yeaaaa hahah she likes you. ;) and she's like the attention. Will your sister not like it if you and her friend hooked up?

[Solstice88]

If I liked my friends brother... I would probably tell her. So... ask your sister?