Why is it wrong to say " a child of six years old" and is possible to say "a six-year-old child"?

Example: My family consists of /is made up of/ is composed of two adults and two children, six years old and ten years old.
But: .... of a six-year-old child and a ten-year-old child?

Can you please recommend me a nice and convenient four-star accommodation in West Yellowstone which lies not too far from the park? Thank you for your help!!

1 answer

There are several ways to say that, but "of" is used the least. It's not actually incorrect; it's simply awkward (has that extra, unneeded word).

... a child of six.

... a child who is six years old.

... a six-year-old child.

Or try this ...
My family is made up of two adults and two children, ages six and ten.

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Can you please recommend me<~~~delete "me" a nice and convenient four-star accommodation in West Yellowstone which lies not too far from the park? Thank you for your help!!

http://www.google.com/search?q=hotels+west+yellowstone+mt&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a
Hotels marked with C, G, and D seem to be the closest ones to the park's west entrance. All would be interesting to investigate, but I'd focus on those three.