Newborn and toddler for dog walks

[Junobug]

I'm going to ask for the earth on a stick here.
I need a pushchair that can take a newborn and toddler and is suitable for a forest walk but I don't want a side by side as I'd like to be able to turn it in to a single when needed. It also needs to be a compact and light as possible. If it could take a car seat for the quick school pick up, that would be amazing but I'm not sure what I'm looking for exists. I'd pay good money if it did. Thank you for any help.

phil and teds dot?

Bugaboo Donkey
Can be used from newborn with a toddler and then as a single. You can also put the car seat on it too. I know a lot of people who have one and describe it as amazing

Stokke Crusi (which you might need to get secondhand as it’s been discontinued). Buy the wheels for the Trailz. Wheels are interchangeable but the Trailz doesn’t hold a sibling seat like the Crusi.

The Joolz Geo 2 sounds like what you're after... a friend has just bought it for similar reasons and is in love with it!

Uppababy Vista?

Oh, far more suggestions than I was expecting. Thank you

Mountain buggy duet V3 can be used as a single - it is a side by side but a narrow one and will last much longer than something like the Donkey, as the seat units are much taller - the donkey seats are soo short - my DD outgrew her buffalo (bigger seats) by height at less than 2.