(CNN) Two of the late President Ronald Reagan’s children are taking opposing stances on same-sex marriage, as Supreme Court justices weigh a federal ban prohibiting marriages between gays and lesbians.

Michael Reagan, a conservative author, defended a controversial op-ed piece warning of a “slippery slope” after same-sex marriage approval during an interview with CNN’s Piers Morgan on Wednesday.

“I think it does send a slippery slope,” Reagan said. “I think if you accept the redefinition of marriage then you’re going to have to accept the redefinition all the way down the line.”

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