Anon's family is in mourning

Not to take the whole thing too seriously, but it really depends on the tradition. Some believe in instant rebirth, some believe there is significant time between births, some believe there's time between births, but only from the perspective of the dead, on earth it's instant. Some believe it's nonlinear, your next life could be a thousand years in the past. There's a whooooole bunch of different ideas around reincarnation, even within the same traditions.