No one remembers Debbie Gibson. Actually, perhaps the opposite is true: Memory is the only way most people experience Gibson anymore, not as an active concern but a blast from the past. Ditto Tiffany, Gibson's sister in late-'80s teen pop stardom. Both singers were ubiquitous from about '87 to '89. Gibson's first album included four top-5 hits, followed up by another #1 off sophomore effort Electric Youth, while Tiffany scored a pair of chart-topping singles from her own self-titled debut. One moment they were pop royalty, the next they disappeared into obscurity. Both kept releasing records all the way up until the dawn of this decade, but in pop cultural terms, they are relics, nostalgic shorthand for another time.