Thinking hard about it.

So me and my husband agreed to wait to get pregnant till next year so I can loose weight to help because I'm a big girl. I had such a hard time trying to get pregnant with my rainbow baby 3 miscarriages 2 dnc and we finally had our baby girl in 2018. Now we found out my grandmother who raised me till I was 13 and I call mom. I feel like I have 2 mom's and my dad wasn't really a dad. She is dying and now I feel like I need to rush. We are pretty sure she isn't going to be here in the next month or 2 because she is declining so fast. I am thinking about going to my OBGYN who helped me with my pregnancy and everything to get all the testing done and start trying now. I just don't know if me rushing now is smart. I know she won't be able to be there for me when I'm having my next baby like she was for my daughter. Should I keep doing what I planed and loose weight then try next year or start now?