andrew as a surgeon she argues with all the time at work, or either him/bill for just a general coworker at the hospital to hang out with since she's at work more than she's at home. i'd also love maybe a friend from summer camp she made over the years who she runs into again as an adult or a couple of truly terrible dates that turned into friendship!
there's no real age in mind, just that he's under 32 and was adopted along with his sister when winnie was a kid. there are two brothers older than winnie, then her, then the adopted siblings. we have a few details for the family worked out but generally they're all close-ish as adults and got along as well as that many kids in one house could get along growing up.