Mama's big boy! On Saturday, Sept. 13, Jessica Simpson shared a major milestone in her son Ace's life with a cute black-and-white snap of her little boy.

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"This stud is 14 months!! Maxi was this age when this handsome man said hello to the world! Omg!" she captioned the sweet picture.

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The tiny tot recently showed off his maturity, serving as the ring bearer at his aunt Ashlee Simpson's wedding to Evan Ross on Labor Day weekend alongside his big sister Maxwell, 2, who was the flower girl.

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By now Ace is used to playing the part after landing the ring bearer in his parents' July nuptials in San Ysidro Ranch. Weight Watchers spokesperson Simpson recently blogged about her new outlook on life, post-babies and marriage, writing, "The walk down the aisle is the beginning of one of the happiest days of your life, and the love you are walking toward is most rewarding when you have that love coming first from within."