Grandma begging for a sleepover

So we are very close with my MIL. She will often take her 3 grandkids, all under 6, for the day. Including my daughter. She has a blast and is always begging to go to grandmas house. Well now I’m due with #2 in October and she will of course be watching my daughter then but she has been begging to start the sleepovers. I don’t know if she’s ready, cause she still is not sleeping through the night. What are your takes on it? Has your child already had a sleepover? I’m not ready for it! Lol