Ahh! Don’t take your toddler down there. Sorry, your question had me flashing back to the catacombs we visited outside of Rome last year. Family brought a two year old with a toy sword and he nearly ruined the tour for the group. He made so much noise (as toddlers naturally do, wasn’t his fault) and babbled the whole time. The guide sent the entire family out at the first available safe exit because he was so disruptive, much to the family’s displeasure but everyone else’s relief.
Not quite the same, obviously, as the Paris catacombs, but having been in them as well, I would really encourage you not to do this.
If it’s something you’d like to do with your daughter, might your wife be willing to wait? There is other stuff in that area to do/see that she could explore during the wait.