Lena is so cute, I would choose something short and spunky to go with it for a girl twin:Ruby Blair Elle/Ella Belle/Bella Rue PearlFor a boy I would go with something masculine but not harsh sounding:Eli Julian August Roman Milo Caleb
Haha I responded to this and then read the other responses, I gave more than one choice for each, but one of my choices was Milo! I think it's soft enough to go with Lena, but still masculine :)