Would your kids tell/let slip your folks, even if innocently done? A secret could be along the line of.. 'it's not a secret for you to keep, but your mom and I would prefer that you not talk about it'. When you reveal, also have your step daughter there to lend support as your wife will. If you have selfies, ask them if they would like to see some of them. I'll bet they'd say YES. Don't dress in front of them unless they ask you to. Then do it nicely. Good luck.
