Feb. 26, episode #3, Mona said she'd been working a lot for Nicole. Leslie said "that's why you've been missing from choir practice". Mona replied that she'd be there tonight by 7:00.
I don't know how they originally met, though. I'm just laughing that Leslie's in the choir.
Mona was originally shown working for Nicole. Later that same episode (Feb. 26) Mona was at Nicole's office. Nicole acknowledged that Mona had been working extra hours. Laura offered to stay late and finish up so that Mona could leave now to go to choir practice. (later that same night, Laura left Nicole's and Leslie ran her off the road).
On the night of Nicole's award ceremony, they said Mona wouldn't be there because she(Mona) was sick, and Eva took on extra work to prepare. We didn't see Mona again until yesterday (April 7), and there was no mention of Mona ever working for Nicole -- that seemed odd to me. I wondered if I had missed or misunderstood something.