Beyonce Knowles ''rescued'' her sister's wedding.

Solange tied the knot with videographer Alan Ferguson last Sunday (16.11.14) but the nuptials nearly resulted in a disaster when the 'Losing You' hitmaker reacted badly to the seafood.

The bride's mother, Tina, said: ''[Solange] went through the wedding and the sit-down dinner and she was just fine, and then they had a second line in the streets of New Orleans and she was dancing so hard, I think she just got overheated.

''And the seafood - she had a reaction to it. So her face broke out in welts.''

The 28-year-old bride disappeared from the festivities for two hours, whilst Beyonce gave her an allergy tablet.

Tina explained: ''[Beyonce] took her back to the hotel and gave her Benadryl and in two hours she showed up at the reception and did the dance with her son and just had a ball.''

Tina, 60, continued to gush about the ''heartfelt'' wedding.

She told Entertainment Tonight: ''There wasn't a dry eye in the place.

''[The couple] were just so heartfelt and I just think the wedding epitomised Solange as a person, and her and Alan's artistic flare.''

Meanwhile, sources revealed that Beyonce and Jay Z had a great time at the wedding, too.

An insider previously said: ''Beyonce and Jay Z were totally into it and so affectionate. They both kept putting their hands on each other's butts and they were dancing up a storm.

''Beyonce and Jay Z were so friendly to everyone and very gracious. They seemed so genuinely happy. They were having the best night.''