We are not going to exclude anybody. If girls want to play, they can. Of course, there is a difference between adult men and women in physicality, which is why there are different leagues for each at the higher level.
As children, there is no point in this. The physical differences between boys and girls are so slight and undetectable, that it just doesn't make any sense to separate children, or prevent girls from having an opportunity to play in the same team as boys if they want to.