Dear Sue, nice to know that Ollie is fine. Lilie and Ollie sounds good, they will learn to co-exist in the same space, but it is absolutely normal that Lilie is jealous of the newcomer. Probably you will have to spend some time with them together, playing or talking to both, they just have to understand that they are loved.
Good luck and plenty of joy with Ollie and Lilie!
Love, Margherita

Two cats by Darcy Daniell