I used to nanny for a family that has 4 kids ages 9 and under. I worked for them for 4.5 years, and left them for a new job a little over a year ago. I've seen them *maybe* twice since then. They obviously got to know me pretty well and vice versa, and they also got to know my now-FI well too. My wedding is end of October 2014.
I ran into the mother at the mall the other day, and she noticed the ring so our discussion eventually turned to the wedding. She knows that both FI and I have large families, and said something along the lines of, "I know we won't be invited to the wedding, but I'd love to go to the shower to celebrate you and FI. So please let me know when that starts getting planned."
I know you're only supposed to invite a person to a shower if they're invited to the wedding, but does that still stand when someone wants/asks to go to the shower and they know not to expect a wedding invite? It would be nice to have her at the shower, but I don't want to be rude!