When Lucy Morris fell pregnant, she and her husband David were given a due date for a week before her sister Emma's wedding, at which she was meant to be bridesmaid.
So they knew they were cutting it fine - but they never imagined labour would kick in on the big day.
However, the 29-year-old primary school teacher woke on the morning of her sister's wedding day with pains in her stomach.
But the bridesmaid kept quiet to avoid outshining Emma.
Lucy, from Doncaster, said: "I was in agony. I just prayed my waters didn't break before they exchanged their vows. I wanted to watch my sister say 'I do' and didn't want to steal the limelight by giving birth."
Her prayers were heard as she managed to keep a brave front, fulfilled all of her bridesmaid duties, walked down the aisle and even posed for the post-ceremony photographs.
She was rushed into hospital during the wedding reception breakfast when the pains were intensified and she gave birth to healthy baby Izzy.
Bride and proud aunt, Emma states: "My day was perfect, the fairytale wedding I have dreamed of my whole life. Having my sister there to to share the majority was all I could have hoped for. Lucy left the wedding breakfast to cheers. It was so exciting. We will share this special memory forever."
By Imrati Anand
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