There was no way Remus would deny Ginny's call for help. Not only did he genuinely care about her, but there was no way in hell that he was going to let Harry down again. Even if Harry had no idea who he was, Remus would be there. He would do whatever needed doing, especially with James so young.
He noticed Ginny mentioned Harry came on his birthday so he stopped to pick up a few things first. He bought a few books and magical toys and wrapped them all in a magically expanding box as quickly as he could before heading to Ginny's. When he arrived, he took a deep breath and reminded himself to focus. He could sit at home with Tonks and let the past come barreling back on him later, not now.
He didn't bother knocking. "Ginny?" He called as he entered the cottage.