Having all three kids in bed with me overnight is generally a sign of intense times. Margaret usually sleeps in her own bed, and Duncan in his more often than not. Still, there are nights when we're all in the big bed, usually because Margaret requests it, which she is more likely to do when she feels stressed. It can make for crowded sleeping conditions, especially when all three kids want body contact with me. It is also wonderful. There is nothing in the world that gives me warm feelings as much as having the three people I love most in the world snuggled up around me. Things will be a bit tight when Warren slips into bed in the wee hours, but he likes having them there too. My lower back may ache a bit when I get up from laying curled around little bodies, but it's nice to wake with the whole family together.
Different people necessarily enjoy different things. In some families, the parents want the bed as their space, and that's OK. Not everyone considers a wiggly toddler the ideal sleeping companion, even people with totally lovable toddlers to cuddle up with. At least my circle of friends understands the whole different things for different people thing, but the idea of kids "invading" the parents bed being a bad thing is just so much a thing that I do think that if I mentioned the 5 people in the big bed thing in the context of a stressful couple of weeks people would assume that I was complaining about the kids in "my" bed instead of using it as an indicator of free-floating stress in the household. If the kids are feeling stressed/sick/lonely and sleeping in the big bed with me helps, that is the sort of thing I like to encourage. Also, when I am stressed I proactively ask Margaret and Duncan if they want to sleep in the big bed because it makes me feel better. I guess that last part is what makes me different from people who see co-sleeping as a burden.