SIL was disappointed last baby was a girl.....DB just announced she's expecting again and just had 12 week scan. He said it was a boy. I was surprised he could know so early and he added, "we're pretty sure it is" and when I spoke to her she said she was actually 13.5 weeks. Crossed my mind that given she was upset last time, they might have selected the sex. AIBU to be thinking this or is it possible to be sure so early?