Promoting one of my bridesmaids to moh

So I have one MOH plus 4 bridesmaids. My MOH and I met freshmen year of college and were inseparable throughout college (sorority sisters, transferred schools together, etc.). When we were in college, we always talked about being each other’s MOHs and I made the promise to her that she would be mine one day. Now that we are a little older, I feel like we have both changed a little bit and aren’t as close as we once were. The bridesmaid who I want to add on as a second MOH has been my best friend since 6th grade. We have been though it all together. But she stayed at home during our college years and during this time, we had a falling out and grew apart - we didn’t talk for almost a year. We ended up making up but I never felt like we were as close as we used to be. She also has a baby and was busy planning her own wedding, so I figured asking her to be my MOH would be putting too much on her. But now months later, I have grown closer with this bridesmaid and feel that we have rekindled our old friendship and I would love for her to be a MOH as well. Would it be okay for me to ask her to be a second MOH or should I just leave it be?