Your sister's account is Tanvi50_?  So whose account is halim50_?  You've sent merits to and received merits from that one as well, and I find it extremely hard to believe that a username format like that one would be used by two different accounts and show up on your merit history.

I think you're a cheater at the very least and probably a blatant liar as well.  The whole "blah blah blah a relative" thing has been used so many times by barnacle-sucking scumbags that it raises a red flag in my mind immediately.