Lucy is fairly popular here, and I’ve seen one or two Lydias but I am yet to hear of a Lillian! Lily yes, very popular. Lillian is my Nan’s middle name. I just don’t know if it’s a bit too old
I don't think it's too old at all. If you go with it, be prepared for her to get the nickname Lily. I personally like Lily, but if you don't, I wouldn't do Lillian.