The mother should be heralded for her heroism by feeding the children
even
though she was probably starved herself.

Nobody was anywhere close to starvation after only a week.
Dehydration is the only risk over such a short period, and if they
could melt snow, that was taken care of.

Mr. Kim was likely already physiologically compromised ...

Not by any lack of food.

... if Mrs. Kim was taking care of the children, he
was probably the one removing the tires and working outside.

The children don't require continuous attention.

If so, he may have been close to physical exhaustion and hypothermia
when he made the decision to walk, and again when he left the road.

I doubt that. He probably simply decided after a week that there were
no search crews looking, or that there was no way of knowing when they
would find them, so in desperation he decided to go outside and look
for help. The decision was not unreasonable; he was just unlucky.
There was a lot working against him, but once they were stuck that
couldn't be changed.

--
Move your sim, and a large fan, into the nearest freezer. It you give you a
new perspective!

Peter