toddler sleepover advice

I was wondering when everyone felt comfortable letting their toddlers go to a sleepover (with a close family member). My mother in law keeps pushing for me to say yes to my 4 year old having a sleep over at her condo. She says she definitely seems ready, but I’m 100% not ready lol. My kids are super close with my in laws, and my husband and I have had 2 overnight dates nights in the past where we stayed at a hotel and my mother in law came to our home and stayed with the kids overnight. Even that I was super hesitant about, but I felt comfortable with my kids being in their own surroundings and sleeping in their own beds and such. I really don’t want to seem like a control freak, but is it wrong to think my 4 year old isn’t ready to sleep elsewhere yet? My MIL keep mentioning how her condo is only 25 minutes away from us and everything. I just don’t feel good about it at all, looking for some honest advice.