Maybe I'm just stupid to assume the best = it's the kids own natural tendency. Parent and child relationship is a difficult matter. Children always emulate their parents, and parents consciosly or subconsiously pressure their kids in every day life. It's hard to say when too much is too much.
Who knows what that child heard, if that woman is an overbearing wife/mother, and he hears her berating his/her father, and is stern with her, "Oh you are such a BOY! Always making a mess and getting into things." and rewarding his sister and or having a soft cooing voice, what would a five yr old want to emulate to please his mum?
Father in that pic looks like a dorky dude. Mother looks to be in control, they even have her sitting slightly higher in the pic it seems...