A brand-new mother's love!
"Jessica is doing great and really happy," the source says of the "Fashion Star" mentor, 31, who gave birth to 9 lbs., 13 oz. Maxwell Tuesday morning in Los Angeles. "She's feeling well and relieved the baby is healthy."
Adds the source, "The baby is beautiful!"
And although many fans are eager for a glimpse of the singer and child post-birth, right now is family time for Simpson, fiance Eric Johnson and their kin.
"The family will be dedicating the rest of this week and most of next week to helping Jess recuperate and take care of the baby," the source explains. "Eric is super happy as well."
Also over the moon? Proud Grandpa Joe Simpson, who now has two grandchildren in Maxwell and Bronx, daughter Ashlee's 3-year-old son.
"Jess dreamed since she was a young girl about being a mom," Joe tweeted Wednesday. "Dreams come true! So happy!"
Noted another insider, "Everyone is marveling at what a natural Jessica is," the source tells Us. "She was born to be a mom!"
MORE FROM WONDERWALL: