Echoing @GU1[name_f][/name_f] it is so common that siblings share similar sounding names. Personally I think [name_f]Gemma[/name_f] is not too similar to [name_f]Georgia[/name_f], you may just want to consider whether you’ll trip over the names in busy moments of parenting or not. (As I always say, 3 of my sisters have two syllable names beginning with C and ending in the ‘ee’ sound and it didn’t cause any problems at all. Two of the names are [name_f]Courteney[/name_f] and [name_f]Cassie[/name_f], for reference.)
[name_f][/name_f]I love [name_m]Max[/name_m], [name_f]Georgia[/name_f] and [name_f]Gemma[/name_f] together, so warm and vibrant!
[name_f][/name_f]To me, [name_f]Gemma[/name_f] is an sparkly (the gem association?) and wholesome. I love the nn option [name_f]Gem[/name_f].