Book about pair of penguins

Chicago Tribune reports:

Savannah, Missouri -- A children's book about two male penguins that raise a baby penguin has been moved to the non-fiction section of two library branches after two parents complained it had homosexual undertones.

The illustrated book, "And Tango Makes Three," is based on a true story of two male penguins, named Roy and Silo, who adopted an abandoned egg at New York City's Central Park Zoo in the late 1990s.

Penguins exhibit instinctual pair-bonding, but that is a lot different from what is commonly called human homosexuality. There were no available females when Roy bonded with Silo. Roy later mated with a female.