Summarizing some previous replies, from my perspective as a father of twins (born 30+ years ago), and now with one having a 2 and a 4 year old, the other a 3 year old. Before there was such a thing as an SUV, we ran with 3 different Chevrolet Astro Vans over their first 18 years - great space, captains chairs in the middle (more on that), space behind the third row (which was a full 3 person wide, and removable), and important as a winter driving and boat towing family, all-wheel drive (after the first 1985 model). We are now on our third XC90, all purchased OSD and all three still going strong, two with us and the "middle one", a 2012, now with the 2 & 4 year old family.
Current situation:
2 & 4 year olds are one front facing, one rear facing child seats. Yes, could be a tight fit for front seat passenger in front of a rear-facing child seat - you'll want to investigate that on either choice of a 90 or a 60. It is an issue.
For XC90 7 passenger, two major things to consider re: child seats:
1) Rear facing seats take up quite a bit of room width wise as well. Only way we could fit three child seats in the middle row was with the Diono car seat, which is quite a nice seat that is narrower than most, primarily due to no cup holders.
2) If you have two (or three) child seats in the middle row, you won't have access to the rear row unless you unbuckle - and possibly remove - one of the car seats to allow you to tip the Volvo seat back to let someone crawl into the third row seats. This issue is often overlooked, and pretty much makes the third row seats unusable unless you have no cargo and can crawl in/over to the third row from the cargo area. On our 2022, we went with the 6 passenger seating arrangement, so can have two car seats in place, and have room to curl in around the forward facing one and then "up the middle" and back into the third row seats.
That is a major advantage of the minivans too, where you can get the kids into the van, along with yourself, and then help them get into their seats and buckled up from "in front" of the seat, as opposed to the XC/SUV method that requires "folding them into a seating position, and them inserting them into their seat from the side/outside of the car. Not great for your back?Along with more cargo space, a minivan is tough to beat for that reason.
I will always go with the safest and strongest vehicle, so Volvo has carried the day for our family of drivers. But with advances in auto safety systems and crash testing to confirm, I think some of the recent minivans are right up at the top with safety ratings and crash worthiness.
So if I had to do it all again (and sort of am, as a grandparent now), here would be my considerations:
1) If likely to be more than a single child family, consider a minivan, at least until out of car seats/booster seats/strollers (so age 7 or 8 or?). If you need all wheel drive, Pacifica and Toyota options seem to get high marks. If front wheel drive adequate, tough to beat the Honda Odyssey (daughter #2 loves theirs). Since we now have one minivan in the family, we're good on that for the moving around of three little ones with 2 or 4 parents. If all 6 adults are going someplace with the kids, it's a two-car journey anyway.
2) re: which Volvo, I'd take the XC90 over the XC60 to be sure- the extra cargo room WILL be utilized, especially when your little one(s) start soccer, hockey, horseback riding, etc. and you have gear that seems to want to just live in the car. And still think I'd seriously consider the 6 passenger option - much easier for kids or adults to get into the available third row seats if you are using that more than just occasionally.