Jessica Simpson's best pal Cacee Cobb has given birth to a baby boy.

The singer's former personal assistant and her 'Scrubs' star husband Donald Faison welcomed their first child into the world in Los Angeles on Thursday (15.08.13).

The 38-year-old actor, who has four other kids from previous relationships, shared his joy on Twitter on Friday night (16.08.13), writing: ''Yesterday @caceecobb and I welcomed the most amazing little boy into our lives! Oh Happy Day!!''

Cacee, 35, retweeted the message, adding: ''The happiest day of my life.''

Donald, who married Cacee in December 2012, previously revealed he couldn't wait to be a father again.

He said: ''I'm just excited for CaCee. She's probably the most loving person I've ever met in my life.

''And so for her to have a baby that she can love and you know, raise, and that we can raise together, and she can influence and teach and stuff like that, it just, I know that it'll be a really good human being when it's older.''

Jessica, who gave birth to her second child, son Ace Knute, with her fiance Eric Johnson, on June 30, threw Cacee a baby shower at the Four Seasons Beverly Hills in early June, just weeks before she delivered her own baby boy.

The 'Fashion Star' mentor, who also has a 16-month-old daughter Maxwell, posed for a picture with her friend to show off both of their growing bumps at the lavish bash.

CaCee appeared to be very grateful for the baby shower, as she later tweeted: ''Showered with so much love yesterday, Thank you @JessicaSimpson #bestfriends #bestbabyshowerever (Sic)''