Demi Lovato takes Wilmer Valderrama as her date to co-star's wedding

HOT SPRINGS, Ark. -- The romance between Demi Lovato and Wilmer Valderrama is heating up.

The singer took Valderrama as her date to the wedding of her former "Sonny With a Chance" costar, E! News reported Monday.

Lovato, 19, served as a bridesmaid as Tiffany Thornton, who played Tawni Hart on the Disney sitcom, married Christopher Carney over the weekend in Arkansas.

Escorted by Valderrama, 31, the "Skyscraper" songstress partied away and in a turn of luck even caught the bride's bouquet at the reception, a possible sign of things to come for Lovato.

Denise Truscello/WireImage

Demi Lovato took Wilmer Valderrama as her date to the wedding of her former "Sonny With a Chance" costar.

The couple, who dated last fall before Lovato's highly publicized breakdown in October 2010, was spotted smooching earlier this month -- alerting onlookers that their relationship was back on.

Valderrama is known as one of Hollywood's casanovas -- he has romanced some of showbiz's most sought-after starlets including his former "That '70s Show" co-star Mila Kunis, bad girl Lindsay Lohan and singer Ashlee Simpson.