Gender question at 12 weeks?

I was just curious, let's say I went to go get an ultrasound done at 12+6 weeks, and had a peek at the genital area of the baby, and its flat, but no signs of the girls 3 lines or a little nub, could that mean its most likely a girl already or just a not so developed boy? Lmao, I'm just trying to give my mom her first grandson after her having 8 granddaughters, no boys. 😂

she's tired of pink.