Katie Couric's Notebook: Barbara Billingsley

In 1956, a 40-something actress appeared in an episode of "Make Room for Daddy."

It was a tryout for the role of Danny Thomas' future wife.

She didn't get the part, but the next year, she took on a role that would make her a legend.

Barbara Billingsley became June Cleaver.

Billingsley, who died over the weekend at the age of 94 was the mother of all TV mothers.

On "Leave it to Beaver," Mrs. Cleaver, was patient, understanding and could be a tough disciplinarian.

She provided the template for a strong and caring maternal presence.

Times have changed, but her influence can be seen even in modern shows like "Modern Family."

Later in her career, Barbara made fun of June's domestic perfectionism, knowing she'd never really be able to shed the beloved character.

As a huge fan of the show, I felt that with the Beav and Wally, I'd been given two extra brothers.

Today, I think a lot of us of a certain generation feel we've lost a MOM.

That's a page from my notebook.

I'm Katie Couric, CBS News.