Okay, I did a brother one. Now hit me with some girls names!
What would you call [name_u]Maxwell[/name_u] [name_m]Alexander[/name_m]’s little sister?
My first thought is [name_f]Beatrix[/name_f]! [name_u]Max[/name_u] & [name_f]Bea[/name_f] 
Maybe:
[name_f]Beatrix[/name_f] [name_f]Elizabeth[/name_f]
[name_f]Beatrix[/name_f] [name_f]Caledonia[/name_f]
[name_f]Beatrix[/name_f] [name_u]Antonia[/name_u]
[name_f]Beatrix[/name_f] [name_f]Catherine[/name_f]
[name_f]Beatrix[/name_f] [name_f]Josephine[/name_f]
Other thoughts on first names for [name_u]Maxwell[/name_u]’s little sister:
[name_u]Maxwell[/name_u] & [name_f]Agatha[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Enid[/name_f]
[name_u]Maxwell[/name_u] & [name_u]Simone[/name_u]
[name_u]Maxwell[/name_u] & [name_f]Sabine[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Ada[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Flora[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Nina[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Margot[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Anais[/name_f]
[name_u]Maxwell[/name_u] & [name_f]Leonie[/name_f]
Hmm maybe:
Maxwell and [name_f]Matilda[/name_f]
[name_u]Maxwell[/name_u] and [name_f]Daisy[/name_f]
[name_u]Maxwell[/name_u] and [name_f]Louisa[/name_f]
[name_u]Maxwell[/name_u] and [name_f]Penelope[/name_f]
[name_u]Maxwell[/name_u] and [name_u]Meredith[/name_u]
[name_u]Maxwell[/name_u] and [name_f]Daphne[/name_f]
[name_u]Maxwell[/name_u] and [name_u]June[/name_u]
[name_u]Maxwell[/name_u] and [name_f]Eliza[/name_f]
I’d pair it with a feminine, modern classic! [name_f]My[/name_f] first thought was [name_f]Adeline[/name_f] 
[name_f]Lillian[/name_f]
[name_f]Audrey[/name_f]
[name_u]Willow[/name_u]
[name_f]Hazel[/name_f]
[name_f]Scarlett[/name_f]
[name_u]Avery[/name_u]
[name_u]Piper[/name_u]
[name_f]Eloise[/name_f]
[name_f]Summer[/name_f]
[name_f]Jocelyn[/name_f]
[name_f]Felicity[/name_f]
[name_u]Vivian[/name_u]
[name_u]Aubrey[/name_u]
Cassia
Delaney
[name_f]Olivia[/name_f]
[name_f]Amelia[/name_f]
[name_u]Madison[/name_u]
[name_f]Hannah[/name_f]
[name_u]Kendall[/name_u]
[name_u]Tatum[/name_u]
[name_u]Kennedy[/name_u]
[name_f]Carolina[/name_f]
[name_f]Molly[/name_f]
[name_f]Madelyn[/name_f]
McKenna
[name_u]Sydney[/name_u]
[name_f]Isabel[/name_f]
[name_u]Jordan[/name_u]
[name_f]Lily[/name_f]
McKenzie
[name_f]Abigail[/name_f]
[name_u]Cassidy[/name_u]
[name_u]Mallory[/name_u]
Maxwell [name_m]Alexander[/name_m] and…
Antonia [name_f]Lucy[/name_f]
[name_f]Georgiana[/name_f] [name_f]Claire[/name_f]
[name_f]Evelina[/name_f] [name_f]Sophie[/name_f]
[name_f]Clarissa[/name_f] [name_f]Emmeline[/name_f]
[name_f]Theodora[/name_f] [name_f]Amelie[/name_f]
[name_f]Rebecca[/name_f] [name_f]Phoebe[/name_f]
Maxwell &
Adeline
[name_f]Clara[/name_f]
[name_f]Elianna[/name_f]
[name_f]Elise[/name_f]
[name_f]Elsie[/name_f]
[name_u]Emilia[/name_u]
[name_f]Emmeline[/name_f]
[name_f]Ivy[/name_f]
[name_u]Josie[/name_u]
[name_f]Julianna[/name_f]
[name_f]Lucy[/name_f]
[name_f]Lyla[/name_f]
[name_f]Nora[/name_f]
[name_u]Ruby[/name_u]
[name_f]Sadie[/name_f]
[name_f]Stella[/name_f]
[name_f]Tess[/name_f]/Tessa
[name_f]Violet[/name_f]
Camilla [name_f]Rose[/name_f]