Relationship Stories for Family Members - Kids, and Toddlers,etc

Trying to choose the correct forum to ask a question is mind-boggling but here it goes. I have two playable Sims they are both playing with non possible Sims in the TAINTED LOVE story. In chapter 4 one of my players got the option of getting engaged and then finally marrying. The other Sims is up to chapter 7 and never got the option to get engaged or getting married. Shouldn't it be the same for each player if they're playing the same story? I wanted the non playable Sims to move in with the playable Sims. Now I feel like one of them is going to get the shaft and not get the option of their boyfriend moving in. What can I do?