Yeah, the lady in red is his mom. At first glace it appears as though he looks like his mom, but if you look really close, he actually looks like his dad. His older sister (the one wearing white) is actually a doctor.
Speaking of moms, and off topic, but i found it really funny in the handsome concert (Lhor Maak Maak? Is that how you spell it?) there was a part where guests were giving the 12 boys flowers right, so the other guys got flowers from actresses, and "special someone", etc. (E.g. Great got flowers from Matt) then suddenly they tease Boy Pakorn because it turns out it's his mother who gives him flowers. So Off (the director) teases Boy Pakorn and gets the flowers on his behalf, then when Boy was about to receive the flowers, Off says something like, "No, your mom says it's for James Ji" then James Ji gets the flowers. It was so funny!