Unsupportive family members

My husband and I have been together 7 years, married for 2. We fell on some hard times and had been living with my parents for a while but almost 2 months ago we finally got into our own place and everything is going very well. We have wanted kids for a very long time but my main concern was getting our house and now that we have it, we have been talking pretty seriously about preparing to TTC. My parents are both totally on board and excited that we want kids, but his parents on the other hand act very hesitant. His mother is always "joking" that when she's ready for grand babies she will tell us... I know of course it's ultimately our decision and our lives, but it sucks knowing she is so worried about it and has negative thoughts about it. She also seems more excited for his brother and his wife when they talk about having kids. I don't know why she acts this way but it really bothers me. We are close otherwise, she just really doesn't seem to want us to have kids... Anyone else experience something similar?