Not a mom.
I started taking Ballet at age 3, and went En Pointe at age 13. At which age I spent 1 year, including the summer months in a Pre-Pointe class, after that I was in the level 1 Pointe class at my studio. I also went to a studio where 13 was the minimum age to go En. I'm now in my early 20's, and I still very actively dance.
As far as age goes, while 10 is young, it's not uncommon for girls that young to go En Pointe. All though I will say that going En Pointe is not something to be rushed. It differs from girl to girl when they are ready to go En, just because you have a class of 12 girls it doesn't mean all 12 are ready at the the same time, for some it's earlier and others it's later.