What do we think of Arthur for baby #4? It’s definitely a boy, by the way!
Other names on my shortlist:
Edward
Flynn
Frederick
Louis
Oscar
I’m not really sold on any of them at the moment. Naming boys is hard! Baby will have two middles and I’ve no idea what they will be either! Halp.
The combination I have is Arthur Frederick Roy.
My other kids are Violet Elizabeth Rose, Hugo Alexander John and Darcy Samuel James.
It’s nice and goes well with the other names
[name_f]My[/name_f] favourite from the list is [name_u]Flynn[/name_u] x
[name_u]Arthur[/name_u] is very charming and classic - it works wonderfully with your set 
Arthur works well, I like it!
I really like Arthur Frederick Roy, but here are some more ideas for middles:
George
Henry
Oliver
Walter
Charles
Peter
Andrew
Walter
Oscar
Simon
Lawrence
Phillip
Charles
Nicolas
Francis
Richard
Benjamin
Joseph
Robert
We definitely have the same taste - my heart actually melted seeing these names together! Absolutely gorgeous sibling names and I love Arthur 
I like [name_m]Oscar[/name_m] [name_m]Frederick[/name_m] [name_u]Roy[/name_u], and [name_u]Arthur[/name_u] [name_u]Edward[/name_u] [name_u]George[/name_u].
I like [name_u]Arthur[/name_u] a lot. It’s cute but stately, a good fit with your other kids.
[name_f]My[/name_f] favourites from your list would be [name_m]Louis[/name_m] and [name_m]Oscar[/name_m]. I just feel they have that slightly funky (but still classic and sophisticated) feel that your other children share.
[name_u]Arthur[/name_u] is a little less funky and a little more cosy to me 
but still a nice fit.
Your list is gorrrgeous! I think [name_u]Arthur[/name_u] is magnificent in this set! Stylistically, my least favorite of your picks is [name_u]Flynn[/name_u], because it hasn’t got as much of a lovely, stuffy-vintage feel as the others. All of the other choices feel right at home in your set! [name_u]Arthur[/name_u] [name_m]Frederick[/name_m] [name_u]Roy[/name_u] is 
absolutely beautiful.
I think it’s a beautiful name, and goes very well with your other kids’ names!
I also love how [name_u]Flynn[/name_u] would play off of [name_u]Darcy[/name_u] having a more surname-y name.
[name_m]Frederick[/name_m], [name_m]Louis[/name_m], and [name_m]Oscar[/name_m] are all fantastic. I do prefer them to [name_u]Edward[/name_u] and [name_u]Roy[/name_u].
[name_u]Arthur[/name_u] fits perfectly with your older children’s names! [name_u]Love[/name_u] it. And I definitely think [name_u]Arthur[/name_u] [name_m]Frederick[/name_m] [name_u]Roy[/name_u] would be a handsome combo.
I am also really liking [name_u]Edward[/name_u] and [name_m]Louis[/name_m] in your set, though [name_u]Arthur[/name_u] still gets my vote overall.
I love [name_u]Arthur[/name_u] but I always think it sounds very mature in [name_f]English[/name_f] whereas your kids names feel a bit more youthful and contemporary, especially with [name_u]Darcy[/name_u] in the mix, so I’d be inclined to pick something that feels a bit more lively. I especially like [name_m]Oscar[/name_m] here, it has a similar feel to [name_u]Arthur[/name_u] but is a bit more friendly, also like [name_m]Frederick[/name_m] a lot as it’s familiar but still somewhat unexpected, also [name_u]Freddie[/name_u] or [name_u]Eddie[/name_u] a cute nicknames!
So while [name_u]Arthur[/name_u] definitely works with your set, personally I like the friendlier vibe of some of the other choices a little more.
all the names on your list are amazing!! arthur is very nice. i love how it’s classic but not dated.
[name_f]Lovely[/name_f] names!
[name_f][/name_f]I think [name_m]Oscar[/name_m] fits best with the siblings, it has a more youthful/lively feel than [name_u]Arthur[/name_u].
[name_f][/name_f][name_m]Oscar[/name_m] [name_m]Frederick[/name_m] [name_m]Louis[/name_m] is a handsome combo.
I think [name_u]Arthur[/name_u] matches perfectly!!
[name_u]Arthur[/name_u] is a lovely name and it fits beautifully with your other children.
[name_f][/name_f]Also love [name_m]Frederick[/name_m] and [name_m]Louis[/name_m]
for me personally I don’t think [name_u]Arthur[/name_u] has the same vibe as [name_f]Violet[/name_f], [name_m]Hugo[/name_m] and [name_u]Darcy[/name_u]. I think [name_m]Frederick[/name_m] would be the best option!
[name_f][/name_f]for a combo, perhaps [name_m]Frederick[/name_m] [name_u]Arthur[/name_u] [name_m]Louis[/name_m]?
Your children have wonderful names and there are no bad options on your list. [name_u]Arthur[/name_u] fits well, as does [name_u]Edward[/name_u], which I would put slightly above in terms of fit. However, I agree with others that [name_m]Oscar[/name_m] does have the slightly less classic vibe of the brothers’ names. [name_f][/name_f] [name_m]Frederick[/name_m] would be great as the first middle name. [name_f][/name_f] If looking for other suggestions: [name_m]Felix[/name_m], [name_u]August[/name_u], [name_u]George[/name_u], [name_u]Max[/name_u].
[name_u]Arthur[/name_u] [name_u]Edward[/name_u] [name_m]Louis[/name_m] is my favourite with [name_f]Violet[/name_f] [name_m]Hugo[/name_m] and [name_u]Darcy[/name_u] [name_f][/name_f]!
[name_f][/name_f]However I am obsessed with [name_m]Oscar[/name_m] [name_f][/name_f]! I think [name_m]Oscar[/name_m] [name_m]Frederick[/name_m] [name_u]Flynn[/name_u] is totally smashing [name_f][/name_f]!
[name_f][/name_f]I like that [name_m]Oscar[/name_m] has the strong O [name_f][/name_f], like [name_f]Violet[/name_f] [name_f][/name_f], and [name_m]Hugo[/name_m] [name_f][/name_f], but [name_u]Arthur[/name_u] has the hard AR sound like [name_u]Darcy[/name_u] so there is cohesive and distinct 2 sounds ( does that make sense)
I like [name_u]Arthur[/name_u] best. [name_m]Alastair[/name_m] and [name_m]Alaric[/name_m] are nice too, as is [name_m]Nicholas[/name_m], [name_m]Gordon[/name_m], [name_m]Lewis[/name_m].
[name_u]Arthur[/name_u] is my favorite from your list so far!