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And now in our Monday documentary, Jane Little continues to explore

what it means to be over 60 in the 21st century, in third ages.

I am James. I'm intelligent. I'm all by your side.

And I am Jane, perhaps an unintelligent human being.

Hello, Rex. I'm very pleased to meet you.

My name is Jane.

You may think that Rex, the intelligent robot, is a toy,

but believe it or not, this creature could be looking after you in 20 years' time.

We are facing the age in population.

So many elderly people now need the nurse.

We just haven't got enough.

So I think the machine will replace human nurse.

In this edition of third ages, here on the BBC,

I'll be exploring what role machines like Rex could really play in the care of older people.

Also a look at what's perhaps the most dreaded disease of old age, dementia.

There are almost 25 million people worldwide with dementia.

And actually, as the age of the population around the world increases,

that's expected to increase to more than 70 million people by 2040.

We hear from a wife what it means to lose her husband to the disease.

Once in a while, they look at you and they'll smile at you until say,

...