Katherine Heigl was worried about "failing" her son by choosing the wrong name.
The '27 Dresses' star welcomed Joshua Jr. into the world three months ago and admits it was really tough to choose a moniker for her little boy.
She said: "I couldn't come up with a name for ages. I don't know why, I just struggled with it. It's a big decision and you don't want to fail this child with the wrong name. I think Joshua is a beautiful name."
As a last resort after the idea had been rejected in the past, the 38-year-old actress decided to ask her husband Josh Kelley if he would be happy for them to call their child after his father and he was thrilled with the idea.
Speaking on Jimmy Kimmel Live!, she added: "One night I sort of approached him with it and said, 'What do you think about a junior?' And he in the past said that he hated that idea and he could never be that guy, but I couldn't - I wasn't finding something that I was responding to.
"And he was like, 'Aw, I love that. That would mean a lot to me.' And I was like, 'Well, maybe had I known that nine months ago I would have had a name sooner!'"
Meanwhile, Katherine - who also has two adopted daughters Naleigh, eight, and Adalaide, five - would love to expand her family and previously confessed that she has "already tried" asking her husband Josh for more kids.
She said: "I've already tried to have this conversation [with Josh], but it's so funny - at eight weeks, he's like, 'I'm not talking about this right now!' I think once you have two, it doesn't matter anymore!"
And Katherine previously admitted her third pregnancy "wasn't planned".
She confessed: "It wasn't planned. I did want to expand our family - we just weren't sure how we were going to do that and I'm all about preparation and planning and timing. Sometimes you just can't do it that way or you get 'surprised' with something and you have to make it work.
"It ended up working so much more beautifully than I ever could have imagined and the fact that we wrapped up filming in December and now I have all this time with him to just be mom ... it's such a blessing. I'm so grateful."