There is the old saying of if your dog sleeps with you, they become the "Alpha".. The reason I say old saying is because new studies have been done and results are out. Dog have no such issues as in if they sleep in the bed, it doesn't make them think they are the "Alpha" although I bet a lot of people still thinks so because of the old school influence. I have read it in an article, reliable and if I can find it, I will post the link but I am pretty busy right now being that it is Chinese New Year Eve today. So don't worry too much about them becoming the Alpha. My dog do not sleep in the bed with me though, he sleeps in his bed right beside my bed and he moves throughout the night, sometimes he goes to the hallway, sometimes under the bed and wherever he likes but when he was younger, he sleeps in his bed for fear that I will dissapear
I am just telling this because a lot of people think they will become Alpha sleeping in bed and even some trainers still believe in that.