Credit: Instagram

Wow, it seems like it was only yesterday that Lisa Wu was still bringing a little bit of sanity to the Real Housewives of Atlanta, but time is flying by! Her son, Justin Sweat, is celebrating a big birthday. Believe it or not, Justin is turning 15! They sure do grow up fast.

Credit: Instagram

Lisa took to her Instagram to gush about her "baby's" big day.

"In less than 2 hours it will b my baby's bday! Happy Birthday @justin2sweat I love u so much!! It is a blessing & an honor 2 b ur mom," Lisa wrote.

Aww! Supportive moms are the best.

She included four pictures with her post: one of Justin as little baby (so adorable!), one of his posing with mama, one of him looking all grown up today, and one of the whole family.

Can you believe her son is almost a man? Share your thoughts on the comments below!