Bus between London mainlane stations

[Dashper]

I've got to get from Kings Cross to Paddington with 4yo DS on 22nd December. We'll have 50 minutes to get the 10.45 train.
Although I've done the journey many times, DS can be a slow walker, so I'd like to avoid the long walk to the tube platform at Kings Cross. Would the bus reliably get us there on time?

Check on the tfl journey planner website. You can type in your journey time and pretences and it will estimate the journey time. I find it generally accurate.

I do think the tube would be quicker.

The bus should take about 30 minutes but you'd still have the same length of walk to the bus stop as the tube platform.

It's also likely to be busier than usual with Christmas traffic so I'd stick to the tube, personally.

Personally, I wouldn't chance it - you have no idea what the traffic will be like. Tube is far quicker.

That's what I was worried about re the traffic. How do I find out which tube line route has the least walking?
I'm reluctant to take a buggy just for this. DH and I normally travel together, so one of us carries DS if needs be but he's coming the next day this time.

citymapper (the app) tells you the tramsfer time between platforms and will also tell you how long the bus will take with current waiting times and traffic. If you have it downloaded it will give you the most straightforward journey on the day and i’d be surprised if it doesn’t have a ‘disabled access’ option aka lifts for buggies etc.

Take the tube - follow the signposts for Hammersmith and City Line and it is 4 or 5 stops directly into Paddington. Much quicker than the bus.