ds was 15 mos when we brought dd home. she mostly slept in a swing, in the living room or in a Nap Nanny in our room. we had a bassinet too . for the first month at least the location didn't matter bc really newborns can sleep through ANYTHING. also, i think i wore dd a lot and she slept on me too
it gets trickier once the yougner one is older (3 mos?) and needs more peace/quiet to sleep. i would move the swing or nap nanny in dd's room, and then close the door and try to get DS to play somewhere else. i had a video/audio monitor to keep tabs on her.