BREAKING NEWS: Sandra Bullock Adopts Baby Girl -- All The Heartwarming Details

Five years after Sandra Bullock adopted her son, Louis, RadarOnline.com has learned that the actress is giving him a sibling! According to sources close to Bullock, she recently finalized the adoption of a baby girl.

One insider told RadarOnline.com that Bullock, 51, has brought the infant home to Los Angeles, and has slowly been taking the newest member of her family out in public.

And with no movies on her slate, according to IMDB, she'll have plenty of time to bond with her baby after the October 30 release of her latest film, Our Brand Is Crisis.

Another insider added that new boyfriend Bryan Randall will be involved in caring for the child.

"Sandra's made it quite clear to Bryan from the start that she's looking for a husband to raise kids with," the source told RadarOnline.com.

"She had the paperwork ready to adopt another child but really wanted to do it with the right man, and Bryan's been checking every box so far."

"Everyone knows how terrified she is of giving her heart away again, but Bryan's incredibly supportive, loving and a brilliant father figure" for Louis, 5, said the source. "Sandra says he's perfect."

Bullock's rep did not respond to RadarOnline.com's request for comment.

Story developing.