You can't make kids play with someone. Author Heather Shumaker says:
Kids are not all friends. Accept social fears and favorites. Guide children toward better friendship skills. . . . Kids are not magically all friends just because they are all little. Young kids are just learning about friendship, and applying the term "friend" to every situation is confusing. Young kids will play with some kids and ignore others. That's OK. As an adult, you don't like everyone you meet, and it's unrealistic to expect a child will have equal feelings toward everyone.