"Happiest of birthdays to this beautiful Texan!," he captioned a black-and-white shot of the couple wearing clear ponchos, gazing adorably at each other in front of Niagara Falls. "I'll celebrate you today and everyday ahead."
Fittingly, East added a red heart emoji to the end of his post after tagging Lambert.
A photo posted by Anderson East (@andersoneast) on
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Lambert's birthday comes about a week before she's set to release her new album, The Weight of These Wings, which features two new songs co-written with her beau.