6 Celebs Who Are Pros At Keeping Their Relationships Private

Some celebrity couples are so good at keeping their relationships on the down low that they should make it a career. From Nicole Richie and Joel Madden to her in-laws Cameron Diaz and Benji Madden, check out which stars are pros at keeping their love life under wraps:

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1. Private Celebrity Relationships: Eva Mendes, Ryan Gosling

Eva Mendes & Ryan Gosling 

This duo has been together since 2011 and just welcomed their second daughter, Amada Lee Gosling, but literally no one knew she was even pregnant until a couple weeks before she gave birth. Mendes and Gosling are experts at keeping things under wraps and we should have known after they had their first daughter, Esmeralda Amada, and didn't say anything until after she was born.

2. Private Celebrity Relationships: Nicole Richie, Joel Madden

Nicole Richie & Joel Madden

Divorce rumors have been swirling around this couple since they tied the knot in 2010, but those couldn't be further from the truth. Although the two appear out and about on red carpets, they barely talk about their relationship in the public eye. "We just get each other. We're both laid-back people. It's never been a job to be in this relationship," Madden told PEOPLE in 2008.

3. Private Celebrity Relationships: Jessica Alba, Cash Warren

Jessica Alba & Cash Warren

Alba and Warren have been together for 10 years but even if they post photos of each other on social media, they never speak much about their relationship to the media. These two are as lovey dovey as the next couple, but we love the fact they keep their personal life on the DL.

4. Private Celebrity Relationships: Penelope Cruz, Javier Bardem

Penelope Cruz & Javier Bardem

Esta pareja is notorious for not speaking about their marriage to anyone besides those in their inner circle so we had to include them. Cruz and Bardem have been married for almost six years and even though they do make red carpet appearances together, but will rarely be caught discussing their personal life.

5. Private Celebrity Relationships: Cameron Diaz, Benji Madden

Cameron Diaz & Benji Madden 

Madden and Diaz got engaged and married before the blink of an eye, so it's clear they like to keep their lives private. Diaz has spoken about her marriage before but in very little detail. "There's no one with a bigger heart than Ben," she said in a recent radio interview. 

6. Private Celebrity Relationships: Cassie, Diddy

Cassie & Diddy

The singer and her mogul boo have been on and off for years but they don't speak out publicy about their relationship. Cassie announced in December that she was single but then posted a photo with him on Instagram a couple of weeks later.