Letting your kids see your cry is perfectly okay and lets them know that's okay for them to cry even as adults.
Your kid may even want to comfort you when you're crying and find out what is wrong and try to make it right for you.
There's nothing wrong with hiding when you're crying because you don't want your children seeing you crying but experts have said that it's actually a good thing for your kids to see you cry.
Everyone cries and it teaches kids that emotions are for everyone and that's perfectly natural and okay for an older kid, adult or anyone to cry.
So if you want to cry in front of your kids it's perfectly safe and okay to do so.