I breastfed my kids. Give the girls six months to a year post breastfeeding to for things to redistribute themselves. Things will firm up and tighten for at least that long afterwards. As far as bras go- I hate underwires with a passion, I've never had one that didn't stab me. I'm not small, single D after breastfeeding and I have a teenaged daughter who is a petite 5'3" with DD. So we have gone through bra misery. I find that cups with no stretch are best with wide minimally stretchy straps. We tend to be very short bodied and high busted so we have to find very short straps as well. Wide bands with at least 4 hooks in the back fortify things best. Yeah we tend to wear pretty industrial looking bras, but they shape and support nicely and believe it or not most comfortably. As a historical re-enactor I find Elizabethan corsets are pretty darn comfy and supporting(not nearly as extreme a victorian corsets, more like a girdle). My daughter would put a good firm shaped exercise bra over her normal bra when she had to run in PE in school. She found that either one alone just wasn't enough to stop painful bounce. She had a couple of the other large busted girls in her class following suit within a month. The normal to flat girls couldn't figure it out until they told them why. These days the effects of being post forty and gravity are definitely taking hold.