no leh....whatever calendar given to me now i count back, not true leh. my sil said got one calendar even accurate up to the day that u conceive. Meaning on certain days is higher chance of getting a gal or boy within the same month. She uses this calendar and also change in her diet and my bro's diet for abt a year in order to get the gender she wants. She finally got 1 girl 1 boy!! For us, we didn't bother, just let nature takes its course and BINGO, another BOY! Seabreeze, we are pals now. heehee. U also stay Bishan right? my neighbour also 2 boys, hmm...maybe Bishan gd fengshui for getting boys? hahaha.