The cute snapshot the designer revealed had a personal touch, revealing two different photographs edited next to each other. The black and white pictures had "3 MONTHS" written on it and showed the blonde beauty holding Ace close, with the bright-eyed boy looking straight at the camera.
Simpson, 33, first debuted the new addition to the family exclusively to Us Weekly in August alongside big sister Maxwell, 17 months. "With two kids, we have our hands full, but every day is a new adventure," Simpson told Us at the time. "It's fun! I feel very at peace with being a mom."
At peace, and in shape! The mom of two revealed her slim post-baby body just two months after giving birth when she stepped out for lunch wearing daisy dukes in Calabasas, Calif. on Sept. 4. She would later be spotted two more times within the month celebrating fiance Eric Johnson's 34th birthday and wearing a sexy cleavage-baring black ensemble during an afternoon family outing.
Simpson officially signed back on with Weight Watchers in August. She reportedly earned $4 million in May 2012 in her first deal with the weight loss company while pregnant with Maxwell. Six months later, it was revealed that she was pregnant yet again with baby Ace!