Breastfeeding one baby but not the other?

So breastfeeding my son lasted maybe a day and then things just got complicated. I wanted to know he was eating so we decided to formula feed. No big deal I’m not mad about it but I’ve been thinking about trying to breastfeed my daughter when she’s born, but I’m feeling guilty. If I didn’t do it for one then is it fair to do it for the other, I believe nutrition is the same, my son is healthy and thriving. It’s nothing to do with giving one “better food” I just feel like to be equal my daughter should get a bottle right off the bat. But I’d like to give her the colostrum atleast. My reason for wanting to breastfeed my daughter is honestly so we can save a bit on formula for a few months. But at the same time I know it’s going to be hard to wean her off once we’re fully committed.

Initial question; is it fair to bf one and not the other? Or should I just stick to the bottle?