the historical past+the past simple

[ostap77]

Could I mix these both tenses when delivering information to a person?

So it gets to the point where we're halfway past the second car.
It becomes apparent that we might hit this truck.
My mom was sitting in the front seat and my sister and I are in the back seat.
And all of a sudden we see this truck and thought we were going to hit it.

[Tdol]

Yes, but where's the mix in the first?

[emsr2d2]

Could I mix these both tenses when delivering information to a person?

So it gets to the point where we're halfway past the second car.
It becomes apparent that we might hit this truck.
My mom was sitting in the front seat and my sister and I are in the back seat.
And all of a sudden we see this truck and thought we were going to hit it.

There's no rule against mixing tenses (many people think there is such a rule but it's a myth). However, if you were telling this as a story, I would be inclined to stick with one or the other.

My mom is sitting in the front seat and my sister and I are in the back, and when it gets to the point when we're halfway past the second car, we suddenly see this truck and it becomes apparent we might hit it.

My mom was sitting in the front seat and my sister and I were in the back. When we got to the point when we were halfway past the second car, we suddenly saw a truck and it became apparent we might hit it.

Either one is fine but I would go for consistency and choose one. However, you WILL hear a mixture from native speakers.

I had a terrifying experience yesterday - I'm in the back of the car and suddenly there was this truck. My mum's sitting in the front shouting "Oh, no, we're going to hit that truck!"

[5jj]

I agree with emsr2d2 up to a point, but I find the mix more acceptable. However, I don't like the mix in one sentence.

So it gets to the point where we're halfway past the second car.
It becomes apparent that we might hit this truck.
My mom was sitting in the front seat and my sister and I are were in the back seat.
or: My mom was is sitting in the front seat and my sister and I are in the back seat.
And all of a sudden we see saw this truck and thought we were going to hit it.
or: And all of a sudden we see this truck and though think we were are going to hit it