I’m...excited! (Please read, I need help!)

So.... there’s a HUGE possibly that I could be pregnant, my period is supposed to be here next week (hopefully it doesn’t show🤞) I got thinking, IF I am and since I’m the last of my siblings to have a kid, what special ways should I tell them? My parents will know RIGHT AWAY, along with my boyfriend. But I wanna do something special for my sister and brother. Then announce it to everyone else when it’s safe in another special way. Does anyone have any ideas on how i should do it when the time comes, even if it’s not this month 😕?