News Humans

A child’s biological sex may not always be a random 50-50 chance

The parent's biology may skew the probability of a baby being born male or female

Smiling family of four outdoors, with a man giving a piggyback ride to a young boy, while a woman leans forward beside them, holding another smiling boy in front.

Having multiple children of the same biological sex, as shown in this family, may be linked to a person’s maternal age being higher when they first start having children.

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By Jake Buehler

Some people may be predisposed to having children of just one sex.