Play differences between boys & girls
Although they are mostly getting along, the play differences are interesting. John runs around pretending to shoot "bad guys" while Rose wants to play with her dolls. I thought we had encouraged our girls to have less gender-defined play roles. Although all the kids tend to separate into play groups by gender when we get them all together and then play games that are more based on gender roles. The girls play dress-up and dolls and the boys tend to play various versions of bad guys or play video games.
There does seem to be middle ground in the games the kids play. Currently, Rose and John have switched to playing campout, where they pretend to go camping. This game seems to be working for them. They have been playing in the girl's room for about 20 minutes without a fight of any kind, so things are holding.
According to a dissertation abstract from Boston College, the differences between John and Rose may as much be an age issue.
Separate regression analyses on three and four-year-olds, and girls and boys, confirmed age and gender differences, and that there were different predictors for social comptence [sic] during sociodramatic play. For three-year-olds the best predictor was play theme, for four-year-olds it was gender, and for girls it was age. Age, gender, peer group and play theme were not predictors for social competence in boys.
Interestingly, this was pretty much the only useful information on this subject the internet was able to provide in a search of Google. Other pages talk about differences, but offer no scientific information on the subject.
As I have taken several hours to write this while watching the three kids, the older two have switched games a couple of times. The most notable game being playing guardians, where they marched back and forth in the hall and asked, "Who goes there?".