Venting needed!

Mary • Married 5/26/12. Police wife. Emergency room RN.
Hi everyone
So my husband and I a ttc#1. We have been married 3 years and been together almost 9 years total. We haven't been trying long but we have yet to get our bfp.
So the reason for my post, and I am not trying to sound selfish at all. Please do not judge me for expressing my opinions on this matter. My 22 year old sister in law is pregnant with her third child, and none of them were planned pregnancies. Her first pregnancy was when she was in high school and they got married a month prior to her first child being born. Don't get me wrong I love my nieces, but it seems like they just get pregnant without any difficulty, like it's catching a cold or something. Now this has been going on for years obviously and I have made my peace with that. I have always joked with my husband that she'll be on her 10th when I am pregnant with our first.
What really got to me today is that my younger sister has been eluding to the fact she may be pregnant. Now I don't know for certain but she just got engaged and prior to my moving away I was the one who administered her depo shots since I am an RN. I can't say for certain she has been getting them. What bothers me is my younger sister needs the spotlight and gets whatever she wants from my mom. (It's a very long story I can't get into). But pretty much her fiancé is unemployed and mooching off of her, not to mention he is a convicted felon (which doesn't seem to bother anyone except me and my husband who is a cop).
It doesn't feel fair. I got married first, have 2 college degrees, just bought a house, and me and my husband have steady jobs. Why is it so easy for people who don't have stability to get pregnant when me and my husband are strategically trying to have a baby. I have wanted a baby for years (since we got married) but wanted to wait for us to be more stable to try. I am not trying to tear anyone down I just need an outlet to express my frustrations.
I thank you to whoever took the time to read this very long post, and I really hope it doesn't offend anyone as that was not my intention. Please do not judge me for expressing my opinions. Thank you again, baby dust to everyone ttc! 💕