(Update: I originally wrote this thinking the younger child was 5 1/2 months old, but in reality she’s 2. Her 5 1/2 month old sib is in another room. That doesn’t change the advice but I did correct the age to be accurate in the first paragraph below.)
Many people have their kids bunking together in the same room. That created problems for one mom who wrote me for advice. Her 5 1/2 month old was stirring at 5:15 am and since she didn’t want the baby to wake up her 5 yr old son, she would come move him out of the room and into her bed. That causes the toddler to have a 20 minute screaming fit.
I want to point out to everyone that even at 5 1/2 months and 5 years we are still dealing with the basics of sibling relations and problem ownership.
Who owns the problem? Why it’s the 5 yr old. After all, he is the one who is being woken up by his 5 1/2 mo old room mate do.
When mom steps in and takes the 5 yr old to her bed, she is not only solving his problem that he owns with his sister, but the perception of the baby is that she is also siding with the older child, because removing him is really sending a message that mom feels his right to sleep superseded her right to get up.
Instead, let the 5 yr old deal with the problem he is having with his sister. He may sleep through it. He may decide to go over and calm her down, he many decide to leave and come to your room on his own. He may crawl into the crib with her and rub her back and they fall asleep together. All are fine, but they are his way of dealing with her. From her perspective she will see how her waking affects her brother rather than how it affects the three of you, which starts getting rivalry dynamics into play.
If he complains to you about her waking you can help him think of solutions, but let him own this problem and deal with it himself. I promise it will have a better result in both the short and the long term.
I can tell you that this mother already tried my advice and reported back success immediately. I hope this helps others, and am grateful for permission to share this tip with other readers.