Theres a guy?

Well I can't give you a correct answer but here is mine anyways. Well if his sister is possibly asked to see if you like him and based on what you put into that conversation, may say you should. Or his sister could be just playing cupid, but I doubt that. She may just want to know because you two are always around and most likely get along with him a lot better I'm guessing with other guys. And for the txting, it may be that because some guys don't know what is the best way to strike up a conversation with the person that he might like. Sorry I don't have much clue as to what else it maybe sorry.