So sorry for your loss 
[name_m]Billy[/name_m] [name_m]Frank[/name_m] and [name_f]Mary[/name_f] Frances…
[name_f][/name_f]Any of the ‘Frank-’ [name_f][/name_f] names could honor both: [name_f]Francesca[/name_f] / [name_f]Francine[/name_f] / [name_f]Francisca[/name_f] / [name_m]Franklin[/name_m] / [name_m]Frankie[/name_m] / [name_m]Francis[/name_m] / [name_f]Francie[/name_f] / [name_f]Fran[/name_f]
[name_f][/name_f][name_m]Bellamy[/name_m] (Billy + Mary)
[name_f][/name_f][name_f]Willa[/name_f] (Billy → [name_m]William[/name_m] → Willa)
[name_f][/name_f][name_m]William[/name_m] (Billy → William)
[name_f][/name_f][name_f]Milly[/name_f] (Billy + Mary)
[name_f][/name_f][name_f]Marley[/name_f] (Billy + Mary)
[name_f][/name_f][name_f]Marianne[/name_f] (from Mary)
[name_f][/name_f][name_f]Miriam[/name_f] (from Mary)
[name_f][/name_f][name_f]Mabel[/name_f] (Mary + Billy)
[name_f][/name_f][name_f]Martha[/name_f] (from [name_f]Mar[/name_f]y and the sounds of Frances)
[name_f][/name_f][name_m]Banks[/name_m] (from Billy and Frank)
[name_f][/name_f][name_f]Bianca[/name_f] (from Billy and Frank)
[name_f][/name_f][name_f]Maisie[/name_f] (from Mary)
[name_f][/name_f][name_m]Marshall[/name_m] (from [name_f]Mar[/name_f]y)
[name_f][/name_f][name_f]Marin[/name_f] (from Mary)
[name_f][/name_f][name_f]Maribel[/name_f] (Mary + Billy)
[name_f][/name_f][name_f]Maris[/name_f] (Mary + [name_m]Franc[/name_m]es)
[name_f][/name_f][name_f]Esmay[/name_f] / [name_f]Esmae[/name_f] (Frances[name_f][/name_f] Mary)
[name_f][/name_f][name_f]Blair[/name_f] (Billy + Mary)
[name_f][/name_f][name_f]Marcy[/name_f] (Mary + Frances)
[name_f][/name_f][name_f]Merrily[/name_f] (Mary + Billy)