importance of legacy connections

Hi all! I am a member of a sorority that's considered top tier at your school (mine too actually.) My younger sister who would be a legacy through me will be coming to your school this fall. She cute, smart and all those things (but a little shy) and I obviously think she'd be a great member for any sorority.

How important are legacy connections to your top tier sororities? Do they carry much weight or none at all? Just wondering if her being a legacy might increase her chances there. Thanks!