So here’s what we did do, and what we may have done differently with the advantage of hindsight!
To do the crossing you have to book a shuttle, as you can only park at the car park at the start of the walk for 4 hours. And they only like you to book the day before, so that the current forecast can be taken into consideration.
Given the current heatwave in New Zealand, we decided that the earlier we could get going the better. So with our alarms set for 5am, Evie decided that she wasn’t going to go to sleep without a drive in the car, nor give us a good nights sleep when she did finally give in!
Still, we were booked on the 6.30am shuttle, so despite our lack of sleep (and Evie clearly wondering why she had been rudely awoken at 5.30am) off we set. And it was the right thing to do.
Given as it was 17degrees that early in the morning, it meant we walked the first 1&1/2 hrs in shade. 
There was still some frost on the plants though! 
and the views spectacular 
And then of course the sun popped out from behind the volcano and we were in the heat of the morning for the ascent.
Lots of steps to prevent erosion both going up and down equals seriously hard work when carrying a Bean!
It was worth it though. Walking through a crater past the lava from the volcano that most recently erupted in 1975. And although it appears barren, the more you looked, the more colours you saw within the landscape.
A big push to the Red Crater summit 
before a careful descent down very loose scree to the lakes.
The lakes were beautiful colours but no swimming allowed as they are sacred. They were also in a very sulphuric smelling area!
From there one last final climb and then a long descent, which became a bit tedious, through steaming hillsides 
and finally some lovely New Zealand forest to shade us from the relentless sun.
In hindsight we would have parked for free at the 4 hr car park at the start of the crossing and walked to the lakes and back again, which we think we could have managed in the 4 hours. It was this side of the walk that was interesting and different with regards landscape.
A totally beautiful walk and very doable with a baby so long as you have the right equipment for all mountain weathers.
Around the world with Evie Bean 