Older boy was about 3 1/4 yrs when the younger boy (@ about 5-6 mths) started sharing the room next to us. Most of the time it works unless DS2 is sleeping and we want to put DS1 in time out. Currently they're about 3 3/4 yrs & 13mths. DS1 doesn't wake to DS2s night feeds / crying unless he's managed to wet his bed around the same time (joys of night training) thankfully that's only usually around 5am
Mine shared a bedroom until about two months ago. They are 10 and 7. They'd shared from birth. They still share at their father's home, but not here. My 10yo is starting to need his own privacy, plus with homework etc it's much easier. They didn't wake each other at all.
My 3 year old and 1 year old share a room. 3 year old has a king single and usually sleeps in it all night. 1 year old has a 3/4 short bed (bigger than a toddler bed, but DS can climb on or off without a step). DS usually starts the night in 'kids room' and comes in to us at some point. We have both been sick but as he gets better I am thinking about trying to settle him in his room again.
DS still feeds to sleep so I haven't had to try to get both kids asleep in their beds. That will be tricky when we get to that point. once they are asleep though, we haven't had issues with them waking each other.
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