Joy-Anna Duggar and Austin Forsyth have said 'I do' in a surprise wedding after being engaged for three months. 

The 19-year-old daughter of Jim Bob and Michelle Duggar exchanged vows with her childhood friend on Friday.  The news was shared by the Duggar family on their official website along with a short teaser clip of the wedding that will air on TLC's Counting On series on June 12.

In the clip, 19-year-old Joy-Anna beamed as she sat hand in hand with Austin, 22, in an understated white lace gown.  Her long hair was worn loose with a pretty veil clipped in at the back. 

'Saying our vows and saying 'I do' and committing our lives to each other is so incredible,' she shared. 'I feel so blessed to be married.'

Austin shared his relief at finally being married: 'I think the moment I said 'I do' is just a huge burden off my shoulder.  Finally being married to her is just a tremendous weight lifted off.' 

Joy-Anna's parents Jim Bob and Michelle also shared their delight over the wedding, saying it was 'an absolutely wonderful day our family will always treasure.' 

'As parents, we could not be more grateful for the godly woman Joy has become, and the loving husband she married! We love you, Joy and Austin and are so happy for you both, as you embark on this exciting journey together!' they said.

Joy-Anna is the fourth Duggar daughter to marry after her sisters Jill, Jessa and most recently Jinger, who wed Jeremy Vuolo last November.  

And the Duggar family isn't done with weddings yet as Joy-Anna's 22-year-old older brother Joseph is all set to marry his girlfriend, 19-year-old Kendra Caldwell, after she accepted his proposal. 

He shared details of the moment he popped the question with People: 'I was definitely nervous going into it but I wasn't afraid that she was going to say no because she has said, 'I'm just waiting on you!''

Kendra was over the moon to be asked for her hand in marriage, saying: 'I'm so happy and so shocked.  There's so many words I want to say, but just shocked.'