Sil and babies

So my sil is pregnant with her first baby. She was really upset that she didn’t have the first grand-baby. So before people come for me. She has no problems getting pregnant, she has the money, she is married and has a 4 bedroom house. But anyway she likes to announce things a month before we have a big thing in our life going on. With our first daughter she got a dog a month before we had her and with our second daughter she got another dog a month before we had her and now a month before my daughter’s 1st Birthday she is announcing she is pregnant. She is like 18 weeks. She had time before this to say anything. I know I don’t dictate when and what people do in their life. I’m just sick of it. Anyway I’m debating on whether or not to have a 1st Birthday party for my daughter because all anyone would talk about is her baby. It’s not about her baby it’s about my daughter and her accomplishments in her first year. Also side note my sister is also pregnant so that makes things even more complicated. So what should I do?