Scenario saves randomly deleted...?

I've been playing the Parenting Predicaments scenario over the past week or so; I spent hours customising the characters/neighbours and building houses.  Yesterday everything was fine, and I saved the game when I closed out of it.

Today I tried to load that save, but I found that both of my scenario saves (stuck in their shadow and parenting predicaments) have randomly disappeared.  My other saves are all still showing up and are playable.

I should also note that my parenting predicaments scenario was incomplete - I don't know if they have a time limit before they get deleted but I completed the other scenario a while ago and that has remained in my saves until today.

Is there a way to somehow get the scenario saves back?

I'd really appreciate some help here as I spent ages on them and would like to keep playing!!