well, milu is 2.6 lbs and 8 months old. she sleeps with me on the bed, but honestly i wouldn't recommend it. just because i think if you have a smaller yorkie, unless she will stay sleeping on top of your pillow or something, i am always worried about crushing her. i started letting her sleep on the bed because i really want to cuddle with her at bedtime. but i regret it now, because she won't sleep anywhere else but on the bed now, and i am always worried about her and i get very mad when my fiance moves around when he sleeps. i always have to stay half awake to karate kung-fu kick him when he moves around. i will yell at him "pick one position for sleeping and stay like that the entire night ok!? you are going to kill milu moving around so much! don't you see how little she is!"
the stairs idea is ok if the yorkie doesn't accidentally fall off the bed. which milu has a couple of times when she slept too close to the edge or when i was playing with her on the bed (another bad idea!)
milu only tried to jump off of the bed once, and she squeaked when she hit the floor...poor baby
i would say if your bed is not too high off the ground. then it's safe (like if you just have the mattress on the floor
) otherwise i wouldn't do it since i think you said your yorkie is also a tiny one.
oh, plus, milu did pee on the bed when she wasn't potty trained yet. but of course that's again my fault for letting her on the bed in the first place.