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Demi Lovato had some special guests in the audience at her hometown concert in Dallas on Monday night. 

The star took to Twitter after performing her "Neon Lights" show at the Verizon Theatre in Grand Prairie.  She posted a photo of her 90-year-old great-grandmother, who posed backstage for a silly shot holding up a peace sign and wearing a tilted, bright pink hat. 

She also had the support of her longtime friend and rumored boyfriend actor Wilmer Valderrama.  Demi posted a shot with Wilmer, as well as his castmates from the TV series "From Dusk Till Dawn," who all flew out to Dallas to watch Demi perform.

The "Neon Lights" tour continues on this week with stops in Houston, Atlanta and Charlotte.