I actually really like Sileo with [name_f]Reverie[/name_f] and [name_f]Caprice[/name_f]! [name_m]The[/name_m] three feel very cohesive to me, all unusual, word-like names with a slightly ethereal/literary quality. Of the two sibsets, I probably prefer [name_f]Reverie[/name_f], [name_f]Caprice[/name_f] & Sileo. [name_f]Cirice[/name_f] is interesting, but I think Sileo fits the overall style of the other two more naturally. Each name also feels quite distinct, whereas Sileo and [name_f]Cirice[/name_f] have very similar beginning sounds.
As for the meaning, I can understand why “to be silent” gives you pause. I don’t think I’d find it inherently condemning, though, especially because Sileo feels quite removed from the [name_f]English[/name_f] word “silent” in everyday use. To me, it has more of a serene, still, contemplative feeling than a “you should be quiet” feeling. I do think the meaning is worth considering if you personally can’t get past it, but I wouldn’t automatically rule the name out because of it.
On its own, I think Sileo is quite wearable. It sounds elegant and distinctive without feeling invented, and I like the soft ending alongside your girls’ names. It also reminds me a little of [name_m]Silas[/name_m] and [name_m]Leo[/name_m] combined, which I think adds to its appeal.
Middle name ideas (feel free to mix and match):
Sileo [name_m]Jude[/name_m] [name_m]Valor[/name_m]
Sileo [name_m]Kit[/name_m] [name_m]Zephyr[/name_m]
Sileo [name_m]Finn[/name_m] [name_f]Winter[/name_f]
Sileo [name_m]Ash[/name_m] [name_m]Orion[/name_m]
Sileo [name_m]Grey[/name_m] [name_m]Caspian[/name_m]
Sileo [name_m]Glen[/name_m] [name_m]Phoenix[/name_m]
Sileo [name_f]Lux[/name_f] [name_f]Vesper[/name_f]
Sileo [name_m]Rune[/name_m] [name_m]Atlas[/name_m]
Sileo [name_m]Rhys[/name_m] [name_m]Legend[/name_m]
[name_f]Hope[/name_f] this helps!