It was also speculated that the party was meant to be the couple's wedding, but it appeared to be about their engagement.
She said: "I've never had a wedding before". She has yet to confirm, however, that they Wednesday leaving her fans guessing.
For the evening, Gwyneth rocked a wine-colored Giambattista Valli Paris dress and a pink corsage on her wrist. We feel like the luckiest people on the planet because we have you in our lives.More news: England reach first ever Commonwealth Games netball final with last-second win
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The traditional attire of the bride, in their opinion, brought mom Paltrow at the entrance to the theatre Blythe Danner was spotted with a garment bag, which bore the logo of a wedding designer Monique Lhuillier.
And Paltrow can't believe her former Glee boss pulled off such a great bash.
One person who was notably absent from the festivities was Chris Martin - ex-husband to Gwyneth and co-parent to their two children - Apple and Moses - but given the nature of the event, it makes sense.