I still feel like I have advice I can share and yet I've needed two csections and have not labored either times. however during both pregnancies I had every intention to birth vaginally and did a lot of research to empower me with information.
My sister will give birth in the next fortnight and wants me in with her. I said of course I'll be there but remember i havnt labored so don't know how much help I could be but she says she still trust and wants my experience.
You should tell your sil I had NO intention of having a cs with my first dd infact I had zero intention of requesting even an epi they both scared the crap out of me.
But life didn't pan out that way and I needed two elective cs