Petty morning rant - SIL be gone

Like I said this is a petty rant because I need to bitch about it, not really asking for advice just venting. I have a SIL that I can't stand. She's always been in this one sided competition with me and my younger sister but mostly myself. I'll give some examples - before I had my first my brother and SIL never came over for the holidays, birthdays etc. As soon as I become pregnant with my first they're so interested in being involved with the family. Even told my mother, after she questioned why they suddenly were interested in coming over they said and I quote "we didn't want you to replace our kids". Oh you mean the kids you won't even bring over but now you're worried she's going to replace them? Okay. When I got pregnant with my first, sil removes her birth control and is pregnant with her third a couple months later. I get pregnant with my second, SIL gets pregnant with her 4th. I say I'm done having kids she ties her tubes and when I announce my third on the way she says she's getting IVF treatment to have a 5th. I'm not kidding. She's insane. My mother at first thought I was exaggerating but now sees it herself. I've always loved Halloween and anything spooky, I'm a big horror fan. She's always been "I'm scared of clowns!" "Halloween is for the devil" "skulls are evil" blah blah blah. All of a sudden she notices everyone gives me Halloween items for birthday/Christmas etc and now suddenly she's "obsessed" with Halloween. She even picked up that I decorate in August so she decorated in July. I'm not imagining this. My mother even said "if I tell her you're taking your kids to therapy for their specialties I know she'll follow for hers that need it because she wants to do everything you do to compete" I can't stand it and it's becoming increasingly annoying. Now she's crying to my brother that she expects the same treatment my sister and I receive on our birthday from our mom..like honey no. Because she doesn't give my mother the same energy when mothers day rolls around but wants the daughter treatment? Like I said I'm simply venting and ranting about something that's irritating me. If you find it stupid that's fine. I'm just over it.