Alchemilla mollis is indeed lovely, I have LOADS everywhere! It CAN get out of hand and start springing up all over the place. If you find it's babies ( and believe me, you will! ) they're easy enough to dig out and transplant somewhere where you DO want them to be, and it will settle in, given a quick drink, quite happily.
But if you wait for too long, it can be a backbreaker to shift, especially if, like me, you're not physically very fit!
Lovely, lovely old plant. Wouldn't be without it.