It is..I do it..ALL THE TIME! ....you can control it sometimes...maybe your daydreams..or if you were thinking of them before you went to sleep then its possible you will dream about them..I dream about Shane every night cus I listen to a WESTLIFE song every night..different things trigger them off. 8)
Every one dreams about themselves every day, so therefore you can dream about the same person every day, and I can even be some one else if you are attached to them or see them often.
If you've fallen in love with someone pretty recently, then it's possible to daydream about them at some point everyday.