It's not unusual for siblings to share a room, whether it be for a few months or a few years. While this can be a source of tension for your little ones, many of the subsequent problems can be prevented. How? Why, with interior design, of course!
Separate the space
One of the best ways to avoid the "She's touching my stuff!" argument is to simply separate the space in a way that makes sense. Your kids are more likely to get along if they're not forced to do so. And if you put in a subtle dividing line in, they will be less inclined to draw one themselves.
Real Simple recommended using a small pocket door to conserve space, but a cheaper alternative to that is to use custom window treatments to divide the room. It doesn't have to go all the way across the room - hang curtains between the beds so your kids feel as though they have some privacy. You should also make a concerted effort to keep their items organized on their designated side of the room - their furniture, clothes, desks etc. It doesn't have to be a perfectly even divide, but by grouping their personal belongings together, you reduce the chance that they'll get in each others' way.
Use creative storage
Keeping your kid's room neat is hand enough when there's only one of them. Throw a partner in crime into the mix and you've got quite the mess on your hands. And on top of that, two little ones crammed into the space room can make spare room hard to come by. Luckily, all of these things can be combated with some clever organization tricks.
HGTV recommended using tall freestanding bookshelves to separate the room while also providing valuable storage space. If you're worried that there will be issues with sharing, put two bookshelves back to back so they have have equal amounts of room.
Under bed storage is another great place to store clothes and toys without taking up too much floor space. Find rolling bins, baskets or install cubbies have have your kids sort their items into each section.
Find a neutral middle ground
Even if it's two girls or two boys sharing a room, they're bound to have different color preferences. If they're not yet old enough to pick a palette, decorate a room in primarily neutral hues. You can inject pigment in a variety of easy ways that can be changed with their tastes - such as discount window treatments, section rugs, wall art and smaller furniture.
If your son and daughter are sharing a room, don't feel the need to paint it pink and blue, right down the middle. Choose a base color that doesn't define a gender, like orange, yellow or green. You could also keep the walls mostly white and off-white and let your children choose the accents for a rainbow of personality.
To make your kids feel as though they still have a special place all their own, take the time to individualize their spaces. It's easy to simply get them matching sheets and room decor, but try to place some of their personal items around the room. For example, you could put large typographical hangings of their first initial in their areas, or have their pillows monogrammed.
You also have the option of catering to their specific interests. If your daughter loves soccer, frame a picture of her with her teammates for her side of the room. If you son likes a certain artist, get him a poster of their most famous work.