[name]Miles[/name]
[name]Bram[/name] (pronounced [name]Brahm[/name])
[name]Tobias[/name] ([name]Toby[/name])
[name]Duncan[/name]
[name]Kirk[/name]
[name]Maximus[/name] ([name]Max[/name])
MN-[name]Robert[/name] (although we have thought that [name]Robert[/name] looks better as the FN for [name]Duncan[/name] and [name]Maximus[/name])
WDYT?
I would do [name]Miles[/name] or [name]Tobias[/name], neither my style, but I think their yours and they go best with [name]Liam[/name].
[name]Miles[/name]- not my style, but not a bad name.
[name]Bram[/name]- sorry, dislike this.
[name]Tobias[/name]- in theory I like it. I love the way it looks but I find it awkward to say. [name]Toby[/name] is cute. I would vote [name]Tobias[/name] if he went by [name]Toby[/name].
[name]Duncan[/name]- not my style.
[name]Kirk[/name]- have a bad association with this name, but even if I didn’t I don’t think I would like it.
[name]Maximus[/name]- I’m sorry, but I think [name]Maximus[/name] is a bit much. [name]Max[/name] isn’t awful, but it’s not my style.
[name]Robert[/name]- I think [name]Robert[/name] would make a good middle name, even though I don’t personally like it.
I vote [name]Tobias[/name] [name]Robert[/name] only if he goes by [name]Toby[/name]. If not, I vote [name]Robert[/name] [name]Miles[/name] (I think it flows better this way). I like [name]Robby[/name] for a nn.
I like [name]Bram[/name], but worry it may be too close to [name]Liam[/name]. I think [name]Tobias[/name] goes best with [name]Liam[/name].
With [name]Liam[/name], I really love the idea of [name]Toby[/name] or [name]Miles[/name] as a little brother! I think [name]Liam[/name] and [name]Max[/name] is great, too, although I’m not sure how well [name]Maximus[/name] fits with the more down-to-earth [name]Liam[/name]. What about just [name]Max[/name]? I think [name]Max[/name] [name]Robert[/name] would be handsome!
[name]Tobias[/name] [name]Robert[/name] is my favorite, followed by [name]Miles[/name], and then [name]Maximus[/name]. 
Good luck!