what would you do?

So hubby and I have been planning all year to start trying for another baby at the end of this year around dec-jan. obviously I know I may not get pregnant right away so there's that factor. But I really want a fall/winter baby. Well my cousin, who lives in Fl. is getting married in Oct of 2018, and I'm in the wedding. (we live in SC) so my thing is, I don't want to be very pregnant or have a newborn and travel that far. (if I was to get pregnant and be due around that time.) my reasoning for wanting a baby later in the year is because our daughter will be 4 and a 1/2 by then, and I want to be able to do things with her the following summer before she starts school. and I feel like that would be hard if I had a newborn in the spring or summer. idk what to do.