Lohans unhappy David Letterman called Ali 'Lindsay'

David Letterman calling Ali Lohan 'Lindsay' during a recent interview this week has caused fury in the Lohan camp.

When Ali appeared on The Late Show Tuesday to promote her new reality show, Living Lohan, Letterman mistakenly referred to the 14-year-old as Lindsay; and the pair both laughed it off.

However, the joke is now over, according to a source close to the Lohan family.

"It's a sticky area because Ali’s rising star is both enabled and discredited by her sister’s notoriety," said the source. "Ali doesn’t want to ride Lindsay’s coattails, and Dina has always believed Ali is a great talent in her own right.

"When he calls her Lindsay, it reminds everyone of how much she emulates her sister’s behavior — she’s basically adopted her voice and look. We can expect it will be hard for Ali to stay out of the tabloids."