Jealous dog during pregnancy?

I have 2 dogs at home, they are very sweet but the older one (she's 4) gets jealous if I pet my other dog (she's 3) and not her. She has never gotten aggressive, she will just push her way through to me but it's almost constant. I'm worried that it will get worse when the baby comes, I'm only 10 weeks but feel like I need to stop this behavior sooner rather than later. Has anyone else had this issue or any suggestions? I'm not sure if training would help because she doesn't act like this when we are around other people or out, just when we lounge around at home