Maman? Papa? Oncle?

Jeanine has provided riddle enthusiasts everywhere with a monster brain twister: When is a child neither his mother's nor his father's son, and yet both his parents' nephew and his foreign sister's cousin? The solution lies not in some maternity ward mix-up, or an incredible case of adoption and mistaken identity. Instead, as Jeanine revealed last week, the answer is found in her delivery in May of a son conceived by in vitro fertilization using an American-donated egg and her own brother's sperm — just eight days before a surrogate mother in Los Angeles gave birth to the baby boy's biological...