The Dirrty hitmaker hit the stage at the Apollo in the Hamptons event at The Creeks, the estate of billionaire philanthropist Ron Perelman, and performed tracks including Lady Marmalade and Ain't No Other Man for guests including Jack Nicholson, Mary-Kate Olsen, comedian Jimmy Fallon, U.S. presidential candidate Chris Christie and New York City Mayor Bill de Blasio.

During the performance, Aguilera decided to give a special shout out to her man as they prepared to mark their baby girl Summer Rain's birthday on Sunday (16Aug15), telling the crowd, "This is a special weekend. It's my daughter's first birthday."

She then dedicated a tune to Rutler, before belting out Etta James classic At Last, reports People.com.

The couple became engaged on Valentine's Day last year (14Feb14). Aguilera is also mum to seven-year-old son Max, from her first marriage to Jordan Bratman, which ended in 2011.

The Apollo in the Hamptons party was organised to raise money for education programmes at Harlem's legendary Apollo Theatre.