Brooklyn Decker broke down in tears when she dropped her son off for his first day at daycare.

The 'Grace and Frankie' actress - who is pregnant with her and husband Andy Roddick's second child - couldn't stop crying in the car on the way home after dropping 23-month-old Hank off.

In a video she posted on Instagram, the 30-year-old star sobbed while saying: ''It's horrible. Oh my gosh, he just walked off, he was totally fine. So bad.

''There was this sweet woman, she just grabbed his hand and he was like, 'OK.' And they just walked away.''

Brooklyn was particularly upset that Hank hadn't even waved her goodbye because the youngster was so excited to start his first day.

The blonde beauty wrote in a caption: ''Hank's first day of daycare was the WORST. For me. It was the worst for me. He was completely thrilled. He didn't even turn to say bye. ''Peace out, mom'' (sic)''

Last month, former professional tennis player Andy revealed the couple - who wed in April 2009 - are expecting a second child.

In a speech at the International Tennis Hall of Fame in Newport, Rhode Island, he said: ''Brook, I don't know how you juggle it all ... You hear a lot of guys find it very tough to walk away from professional sports, but you are the reason my personal transition into a quasi-everyday life has been gratifying and full.

''Hank will someday realise how lucky he is, and our daughter that's coming will also realise she has the best mother on earth.''

When Brooklyn was expecting for the first time she couldn't get enough of orange juice.

She previously said: ''My only weird craving - it's not even weird - is orange juice. I've never really enjoyed orange juice but it's my one craving.''