Exactly! This is the reason the rule of thumb about outing people exists and this answer completely breezes by it as if there's no possibility whatsoever that the other parent could have any considerations besides her right to dictate whether her kid is sexually active! For that matter, "it doesn't sound as if the mom will absolutely forbid her daughter to see yours" already seems to realize that that's a possibility and again ignore it, like it would be acceptable but regrettably necessary to snitch on a child if you did think it would likely result in them being "forbidden to see" your kid anymore!