How long did it take your old cockatiel to like the new one?

Hello! I have a sweet cockatiel and recently got a second cockatiel to keep her company. They’re both females the new one loves her and will come up to her and bow her head or try to rub it on her but my bird just pecks at her. They’ve been together for over a week now and my bird isn’t warming up to her. She’s civil but pecks if she comes too close. Do you think she’s gonna warm up to her?