1)I am 24 and can't keep away from temptations,i am engaged to a girls since two years and want to marry now but her parents want her elder sisters to get married first.What is islamic ruling on it? 2)When I saw her,started liking her but got to know that someone else was interested in her, i then asked my mother to ask for her hand,which her parents replied in affirmative,is this alright,she was not engaged before but her aunt wanted her for her son ?

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

One should not delay marrying off a girl when a competent and suitable man proposes to her on the grounds that her elder sisters are not yet married. The Prophet said: “O 'Ali, there are three things which you should not delay: “The prayer when its time begins, the funeral when the body of the deceased is ready, and marrying off an unmarried woman when a suitable match is found for her.” [Al-Haakim]

As regards you proposing to this girl while knowing that someone else wants to propose for her, then this is permissible as long as the other person has not yet proposed to marry her; for more benefit, please refer to Fatwa 91435.

Finally, we advise you to talk to whomever you think may intercede for you with the father of this girl to expedite the marriage.