1. As thick as thieves.

2. Lately Nick and Lou have been as thick as thieves.

3. Then they'd be as thick as thieves again.

4. We are brothers as thick as thieves.

5. They are as thick as thieves , down to the last second cousin.

6. They have been as thick as thieves for all of their lives.

7. I'm sure she tells Ruth everything we say - they're as thick as thieves, those two.