updated 06/15/2011 AT 11:00 AM ET
•originally published 06/16/2011 AT 8:30 AM ET
The Duggar family just got even bigger – it’s a boy for Josh and Anna!
Josh, 23 – the eldest son of Jim Bob and Michelle Duggar – and his wife welcomed a new addition on Wednesday, four days earlier than expected, a source confirms to PEOPLE. The couple are not ready to release the name publicly yet, but they are staying with the “M” theme.
Weighing in at 8 lbs., 5 oz., he joins big sister MacKynzie, 20 months. And he’ll have plenty of doting relatives with 18 aunts and uncles – Jim Bob and Michelle’s children – whose lives are documented on TLC’s 19 Kids and Counting.
Anna, 22, gave birth at 5:55 p.m. in the family’s Tontitown, Ark., home, the same place MacKynzie was born.
“I think of Josie being born at only 25 weeks,” Josh told PEOPLE prior to the birth, “and it makes us think about how precious life is and what a blessing each child is.”
For more on the latest Duggar addition, tune-in to 19 Kids: First Grandson this Sunday at 8/7c on TLC.