Quick Airmiles Q?

Hi All.
Just a quick one. My wife has a FC Account with around 9000miles in it. I have just shy of 200k in mine. Can I use her miles as well as mine on a reward booking if we are both travelling together? Or is this something that is reserved for Gold members?
TYIA

Yes, we do it all the time, but it needs to done in whole journeys. Can't just say take 90k from one and 5k from the other.
I think the perk for Gold members is that you can have a joint account. Being a lowly Red I haven't looked into that.

Dick D