Need advice on confronting MIL?

My husband has one older brother and my in laws are OBSESSED with the older brother (Tom). We are 30, and Tom is 35. We are all grown, married adults, but my MIL is still playing favorites. She talks about Tom and his wife non-stop, she goes over their house multiple times a week, buys them groceries and makes them meals, and brags about their very regular, typical jobs. She acts like Tom and his wife are God’s gift to this Earth and she barely acknowledges my husband. She often tells us she can’t do something with us because she has to visit Tom. Throughout our whole wedding planning process she talked about how wonderful Tom’s wedding was (it was in her backyard! Of course!) And she told me she couldn’t wait for Tom’s daughter to steal the show from me on my wedding day, because she is just the most perfect child. Now I am pregnant and she can still only talk about Tom. I asked her for baby pics of my husband and the only one she gave me is one of Tom sitting on her lap, around 5 years old, she is smiling down at Tom, and my husband is a crying baby on her other arm. That’s the only one she chose! Also, when my mom called her to tell her she was planning my baby shower, my MIL immediately responded with, “Tom has a game that day”. (Tom is a high school basketball coach). Again, more concerned about Tom, and still going to his “games” when he is a 35 year old coach. She knows all of the stats of all the players on Tom’s team, but she can’t even explain what my husband does for a living. (even tho he has explained it to her multiple times). She wants to go watch a high school basketball game instead of coming to the baby shower for her grand baby.

So, I want to say something to my MIL. I want to tell her enough is enough! But whenever I bring it up my husband just says, “I know. I’ve been dealing with this my entire life. She doesn’t pay attention to me. It’s fine. Just let her be”. I can’t stand it tho! I can’t stand to see my husband STILL constantly be “second place” to his brother. It has gotten to the point where I am uncomfortable spending any time with my MIL because all she does is talk about Tom.

Should I confront my MIL? Especially since I am pregnant? Try to stop this behavior before the baby comes? Or should I listen to my husband and just let his mother be the way she is. Any ideas?