"Rockwell and I so appreciate all your warm wishes!" Liu captioned the pic, posted a week after announcing Rockwell's arrival.
For more on Liu welcoming Rockwell earlier this year, check out the video.
See photos of Lucy Liu's roles:
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Lucy Liu, Stills from her work
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Lucy Liu shares sweet pic of her baby Rockwell
(Photo: Jeff Daly/USA Network)
(Photo credit: Jeff Daly/USA Network)
NEW YORK - APRIL 30: 'Absconded' -- Holmes and Watson look into the death of a member of Holmes' online beekeeping community who was a researcher looking into a deadly Northeast honey bee outbreak. During the investigation, they meet Tara Parker, a brilliant entomologist, academic and the leader of New York's beekeeping society. Also, Captain Gregson enlists Watson's services in an off-book investigation that helps him make a life-changing decision, on ELEMENTARY, Thursday, May 7 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Pictured (L-R) Jonny Lee Miller as Sherlock Holmes and Lucy Liu as Joan Watson (Photo By Jeff Neumann/CBS via Getty Images)
NEW YORK - APRIL 30: 'Absconded' -- Holmes and Watson look into the death of a member of Holmes' online beekeeping community who was a researcher looking into a deadly Northeast honey bee outbreak. During the investigation, they meet Tara Parker, a brilliant entomologist, academic and the leader of New York's beekeeping society. Also, Captain Gregson enlists Watson's services in an off-book investigation that helps him make a life-changing decision, on ELEMENTARY, Thursday, May 7 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Pictured (L-R) Jon Michael Hill as Detective Marcus Bell, Lucy Liu as Joan Watson, Jonny Lee Miller as Sherlock Holmes and Sutton Foster as Tara Parker (Photo By Jeff Neumann/CBS via Getty Images)
NEW YORK, NY - AUGUST 17: Actress Lucy Liu on the set of 'Elementary' on August 17, 2015 in New York City. (Photo by Bobby Bank/GC Images)
NEW YORK - MARCH 5: 'A Stitch In Time' -- Holmes and Watson (left Lucy Liu) investigate the murder of a professional skeptic, a man who debunked paranormal, religious and scientific phenomenon for a living. The case becomes urgent when his homicide reveals a potential threat to homeland security. Also, Captain Gregson's daughter and fellow NYPD officer, Hannah (right Liza J. Bennett), asks Watson for help with one of her cases, on ELEMENTARY, Thursday, April 16 (10:00-11:00 PM, ET/PT), on the CBS Television Network. (Photo by Jeffrey Neira/CBS via Getty Images)
NEW YORK - JANUARY 7: 'Seed Money' -- While Kitty tries to find a runaway teen, Sherlock and Joan work a case in which the murder of a brilliant bioengineer looks to be at the hands of a drug cartel. Also, Joan makes a major life decision but worries it will impact Sherlock negatively, not knowing that Sherlock has big news of his own, on ELEMENTARY, Thursday, Jan. 15 (10:00-11:00 PM, ET/PT), on the CBS Television Network. on the CBS Television Network. Pictured Lucy Liu and Joan Watson (Photo By Jeff Neumann/CBS via Getty Images)
NEW YORK - APRIL 23: 'The Best Way Out Is Always Through' -- When a judge is murdered, Holmes and Watson become involved in the interstate search to find the prime suspect, an escaped convict from a privatized prison. Also, when Holmes applies his deductive reasoning to Detective Bell's new relationship, the romance hits a rough patch, on ELEMENTARY, Thursday, April 30 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Pictured (L-R) Lucy Liu as Joan Watson, Jonny Lee Miller as Sherlock Holmes and Jon Michael Hill as Detective Marcus Bell (Photo By Jeff Neumann/CBS via Getty Images)
LOS ANGELES - FEBRUARY 17: 'For All You Know' -- When Holmes is implicated in the murder of a woman who was killed during the height of his addiction, he investigates himself to find their connection. As Holmes retraces his steps with Watson's help, the clues make his confidence in his own character waver, on ELEMENTARY, Thursday, March 5 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Pictured Lucy Liu as Joan Watson (Photo By Jeff Neumann/CBS via Getty Images)
NEW YORK - JANUARY 30: 'One Watson, One Holmes' -- Holmes and Watson find themselves in the middle of a civil war being fought on the Internet when a member of Everyone, the anonymous hacker group they periodically work with, is murdered, on ELEMENTARY, Thursday, April 9 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Pictured (L-R) Lucy Liu as Joan Watson and Jonny Lee Miller as Sherlock Holmes (Photo By Jeff Neumann/CBS via Getty Images)
NEW YORK - SEPTEMBER 29: 'The Adventure of the Nutmeg Concoction' -- A bored Sherlock forces his investigative services onto Joan, who is trying to locate a woman who has been missing for five years, and the only clue is the smell of nutmeg at the site of her disappearance. Meanwhile, Joan's bond with her long-distance boyfriend, Andrew, is tested when a man from her past reappears and asks for her help, on ELEMENTARY, Thursday, Dec. 11 (10:00-11:00 PM, ET/PT), on the CBS Television Network. Pictured Lucy Liu as Joan Watson (Photo By Jeff Neumann/CBS via Getty Images)
381311 02: Lucy Liu (Alex), Cameron Diaz (Natalie) and Drew Barrymore (Dylan), left to right, star as a trio of elite private investigators in Columbia Pictures'' action-comedy, 'Charlie''s Angels.' (Photo by Columbia Pictures/Newsmakers)
381311 05: Drew Barrymore (Dylan), Cameron Diaz (Natalie) and Lucy Liu (Alex), left to right, star as a trio of elite private investigators in Columbia Pictures'' action-comedy, 'Charlie''s Angels.' (Photo by Columbia Pictures/Newsmakers)
HOME IMPROVEMENT - 'Bachelor of the Year' - Airdate: February 7, 1995. (Photo by ABC Photo Archives/ABC via Getty Images)
LUCY LIU (FOREGROUND) WITH EXTRAS
