[ferretchucker]

What got me thinking was the line "You've been in my life so long...blah blah blah etc." [in relation to the alien]

Ripley's personal timeline goes...

Events of the Nostromo (about 2 days?)
hypersleep (which presumably just feels like a normal sleep)
About a week on the space station recovering
Events of Lv-426 in Aliens (Again, 1 day?)
Hypersleep
Events of Alien3 (2-3 days?)
Death - cloning (instaneous?)
Events of Alien: Resurrection (for her from cloning, maybe a fortnight?)

So really, by the time she delivers that line, in her conscious timeline, it's only been about a week and a half since Kane's baby was born. By the end of Resurrection it's only been about a month. I just find that quite interesting to mull over, considering it's never really addressed in the films.