> that the other child is not a (son AND Tuesday-born), that's when the 13/27 arises. No. The other can be (son AND Tuesday-born) as well and the probability i

> that the other child is not a (son AND Tuesday-born), that's when the 13/27 arises. No. The other can be (son AND Tuesday-born) as well and the probability is still 13/27. See Colin's reply to me.