No there is nothing magical about age 3. If co-sleeping is still working for you, your spouse and your son, there is no urgent need to change anything. It is true that 3 year olds look more like kids than they look like babies. Perhaps if you had a second child at this time, you'd be more eager to move this little guy into his own space. However, if you can sleep well with him next to you and he can sleep well and your husband has no strong objections, you can safely continue this arrangement for another couple of years. You might help your toddler make a transition to his own space some time over the next year or two by offering him a small mattress on the floor in your room and then gradually weaning him into his own room. You don't want a really big boy in the parental bed room for reasons of modesty. If a parent waits too long to help a child separate, the child can really have unnecessary fears of separation later on. However, the matter is not urgent. You can get his room all set up for him in a way that makes it appealing and let him take naps there or start off sleeping there in the night. Gradually increase the amount of time he spends there until he feels like it is "his" space. The transition can feel natural and positive when everyone is ready for it.   Sarah Chana