It’s all a bit complicated from an international point of view, so here are the dates. I recommend forwarding this link to your boyfriend/husband/father-of-your-children, so there is no confusion possible. And if your children have their own email address, it’s best to email them too.
If they are in doubt about the correct date, I suggest advising them to celebrate twice. It’s always better to be safe than sorry…

xxx Esther