My DS has a real 'it's my way or the high way' attitude when it comes to playing with his friends. He's desperate to have a best friend, but when they come round for tea, his friends often end up playing with his very affable, compliant little sister and he ends up on his own.
The problem with DD is that she's very lovely and easy going. That's made DS used to dictating play, and his friends like that she'll play what they want (she's 4yo).
My attitude is, and always has been, to let my DCs and their friends get on with it and sort out their own problems, and intervene only if needed. But I'm worried DS will end up friendless, and it makes me feel a bit sad. He plays very well on his own, and I'm glad that he goes off on his own rather than throwing a tantrum if things aren't going his way. I just think a bit of empathy and compromise wouldn't go amiss.
Maybe he's too young for me to worry and I should let him work it out for himself? We don't let him get his own way generally. I'm quite strict, and he's very well behaved on the whole.