Christine's stepmom and Meri's half-siblings

I don't watch the show (but did watch the pilot years ago and do sometimes listen to reaction videos/tik toks), so questions:

1) Has Christine's other mom ever been featured on the show? If so: which seasons/episodes?

2) I thought that was in the pilot, but I can't find it: Meri mentioned that her father had 5 wives and how many kids Bill Barber had with each wife. I cant find that now. :( Can anyone help, please?

Something else: I was today years old when I realized that Meri's stepsister is married to Robyn's stepbrother!

I was also today years old when I realized that Meri's full sister was the same age as her oldest stepson from her sisterwife...