Middle names are set for family reasons.
[name_m]Ambrose[/name_m] [name_m]Arthur[/name_m]
[name_m]Sylvan[/name_m] [name_m]Arthur[/name_m]
[name_m]Isidore[/name_m] [name_m]Arthur[/name_m]
[name_u]Winter[/name_u] [name_m]Arthur[/name_m]
[name_f]Sigourney[/name_f] [name_u]Allison[/name_u]
[name_f]Renata[/name_f] [name_u]Allison[/name_u]
[name_f]Bernadette[/name_f] [name_u]Allison[/name_u]
[name_f]Maude[/name_f] [name_u]Allison[/name_u]
[name_f]Severine[/name_f] [name_u]Allison[/name_u]
I like [name_m]Ambrose[/name_m] and [name_f]Renata[/name_f].
[name_u]Vesper[/name_u] is an unusual name so I think the names I hear the least in real life are [name_m]Sylvan[/name_m] and [name_f]Renata[/name_f]. I love the saint names of [name_m]Ambrose[/name_m] and [name_m]Isidore[/name_m] but they may be too conservative with a sister named [name_u]Vesper[/name_u]. [name_u]Vesper[/name_u] and [name_u]Winter[/name_u] are too matchy as are [name_f]Bernadette[/name_f] and [name_f]Severine[/name_f]. [name_f]Maude[/name_f] is clunky and [name_f]Sigourney[/name_f] is too strongly associated with the actress.
I absolutely adore [name_m]Ambrose[/name_m]! Its one of my favorites, but I don’t know if I’d dare use it in real life. I’d swoon if I heard it on a little boy!
From the girls I definitely like [name_f]Bernadette[/name_f] and [name_f]Sigourney[/name_f] the most… Since you like [name_m]Isidore[/name_m] have you considered [name_f]Isadora[/name_f]? I love love love [name_f]Isadora[/name_f]!
Cool names! To go with [name_u]Vesper[/name_u], I prefer
Boy - [name_m]Ambrose[/name_m] [name_m]Arthur[/name_m] (super handsome and uncommon yet still familiar) or [name_m]Sylvan[/name_m] [name_m]Arthur[/name_m]
Girl - [name_f]Renata[/name_f] [name_u]Allison[/name_u]
Good luck!
@mischa, I feel the same way about [name_u]Vesper[/name_u] and [name_u]Winter[/name_u].
[name_f]One[/name_f] of the main problems is that I KNOW many berries will like [name_m]Ambrose[/name_m], and it is really the one I like most (tied with [name_m]Isidore[/name_m]) and it’s must husband’s favorite. The catch is that it is the name of a college friend of his who died in a very unfortunate way (drug overdose) and he has concerns that there is a certain segment of our friend group from that time in his life who will have that immediate association. For the most part I think they will get a new association, but I can see his hesitation.
@Inky, I do like [name_f]Isadora[/name_f] but the [name_f]Dora[/name_f] nn potential isn’t my fave and I have a policy that I really must accept all nn possibilities for a name I choose 
I love [name_f]Sigourney[/name_f] too! It’s my tops! But I do have a fear that as micha mentioned it will be only associated with the actress.
I agree with the others in [name_m]Ambrose[/name_m] or [name_f]Renata[/name_f]. They sound the best with the middle names you selected. As far as your husband’s friend, I see no harm in honoring a friend who passed away because they were a good friend for their life, not their death.
[name_m]Sylvan[/name_m] [name_m]Arthur[/name_m] is nice
[name_u]Winter[/name_u] [name_m]Arthur[/name_m]. I don’t like the flow this, and I think [name_u]Winter[/name_u] is too feminine for a little boy. However, I like [name_m]Winters[/name_m] for boys. [name_m]Winters[/name_m] [name_m]Arthur[/name_m] is very nice.
Thanks again for all this input!
@justanamelover Ohhhhhhh I Really like the name [name_m]Winters[/name_m] as an alternative!
Oh, I adore your names.
I would eliminate [name_u]Winter[/name_u], only because the sound is a little too matchy with [name_u]Vesper[/name_u]. [name_m]Ambrose[/name_m], [name_m]Sylvan[/name_m], and [name_m]Isidore[/name_m] have the same silvery, magical quality as [name_u]Vesper[/name_u]. From your girls’ list I like [name_f]Renata[/name_f] and love [name_f]Severine[/name_f]. [name_u]Vesper[/name_u] and [name_f]Severine[/name_f] would be absolutely perfect together. Seriously, I can’t think of a better sibset.
[name_u]Winter[/name_u] (or Winterson) and [name_f]Renata[/name_f] (or Sebastienne) are lovely.
I like [name_m]Ambrose[/name_m] the best. I agree with [name_f]Augusta[/name_f] [name_u]Lee[/name_u] [name_u]Winter[/name_u] seems matchy with [name_u]Vesper[/name_u]. (I wish [name_u]Winter[/name_u] was going for boys but it’s not. Sigh.)Have you thought about [name_m]Winston[/name_m] or [name_u]Winslow[/name_u]?
[name_f]Renata[/name_f] is on my own favorites list. [name_f]Love[/name_f]!
I also like [name_f]Bernadette[/name_f], [name_f]Severine[/name_f], and [name_f]Sigourney[/name_f]. [name_f]Maude[/name_f] seems too dated next to [name_u]Vesper[/name_u].
I don’t anyone with any of these names except one [name_f]Renate[/name_f].
Good [name_m]Luck[/name_m]!
@augusta I love [name_f]Severine[/name_f], too…my only hold up is the meaning ‘stern’ or ‘serious.’ [name_m]How[/name_m] can I spin that in my mind!