If you are pregnant with your 2nd + baby and know the sex, was your second baby the same sex as your first?

I know there isn't much truth to these things, but I hear that women are more likely to conceive either boys or girls based on their acidity levels (not just the XX or XY sperm alone). I am just curious, if you have had 2 kids or are far along in your pregnancy with your second (to where you know the sex), are they the same or different? Is it a straight 50/50 chance, or if you have 1 girl, are you more likely to have another girl? If you have a boy already, are you more likely to have another boy? Thoughts?