Sims, Cant Marry?

Hi! Im a new sims mobile player and I have two roommates in my house. My player, and My other player. Both of my players have recently gotten engaged with other npc’s and my main player is currently completing the “Do you take this menu?” marrying quest. I want my other Player to do this too, but it says please participate in the wedding quest. I understand my other player is participating in the quest, but how do I get her to participate too?