Pregnant Alex Cooper sported her baby bump at her brother Grant Cooper's wedding ... and we've got photos!

Check it out -- Alex slipped into a loose-fitting gold and white dress composed of a satin-like material to support her bro on his special day.

She looked happy to be out and about with her friends and fam ... though not as happy as Grant who had a starry-eyed grin across his face as he stepped out of Saint Elizabeth's Church in Edgartown, Massachusetts on Saturday after tying the knot with Emma Hayes.

Grant opted for a classic black tux for his special day, while Emma wore a ballgown with a sweetheart neckline and a ruffled skirt. Sweetly, their vows took place exactly one year after he asked for her hand in marriage.

As you know ... Alex got married to Matt Kaplan in April 2024 -- and Grant officiated their ceremony. The media mogul and Matt announced their pregnancy in May.

As we've reported ... all eyes have been on the couple as they've both been subject to claims they contribute to a toxic work environment at their company, Unwell.

The pair have ignored the drama ... after all,. they're too busy celebrating the happy couple!