Travelling with 2yo & 1yr old

[TooBusyGazingAtStarss]

I need to travel from Essex to Scotland for a wedding.
I have a 2 year old and 1 year old - how do i do it?! - with my partner also.
Ive looked at flights but it was nearly £700 including car hire with car seats which I can't afford..
driving that far with such small children - like 7 hour journey + stops?! - surely is a bit much?
The train isn't really an option because I can't pack light and would have an hour n a half train journey just into london..

Ive kinda left it that the kids won't be coming but its such a shame.. any ideas?

Will they sleep in the car? If you can rely on that driving isn't So bad. Leave at 3am drive halfway, stop for breakfast and something energetic for an hour or two, then drive the rest, and more running around time before the wedding. Stay over one night, drive two hours towards home, do some kind of fun day out, teeth and pyjamas after dinner, and drive home.

If they don't sleep in the car (mine didnt) you take time off work and stop for a night half way up/back. It sounds excessive but cheaper than flying and was so much less stressful for us.

How far into Scotland is it?

All have dinner early with the kids, put them in the bath and PJs and hit the road. Hope / pray they sleep in the car.
Book the cheapest Premier Inn that's a few hours from home and break the journey there overnight.
Big breakfast and a run around before you leave the next morning. Stop somewhere at a tourist attraction for a few hours to break the drive. Arrive in Scotland that evening for the wedding the next day.
Repeat in reverse. But it does turn it into a long time away compared to a couple of hours to fly.

Through the night or a road trip adventure calling at playgrounds indoor play areas on the way

Break the journey up.

We've started at 7am before, driven for an hour then stopped for breakfast.

Find a national trust or something similar half way to spend some of the day.

Stop for dinner / perhaps stop overnight in a cheap premier inn.

I wouldn't be put off by the driver. I would get up very early in the morning and start then stop for a decent run around every few hours. Overnight stop two thirds of the way would help but may not be necessary.