I got my BFP today at 13 DPO


At 13 DPO I got my blazing BFP. But I can’t tell anyone (except my hubby) b/c my sister is 27 or 28 weeks pregnant and at 20 weeks she found out that her sweet baby girl has CDH and she was crushed. She leaves February 5th to go to St. Petersburg where the best doctor in the nation is to wait to deliver her baby. It would absolutely crush her right now if I told her I was pregnant. This is my 3rd baby. She would probably think it was to take all the attention from her or revenge. It’s really not but she won’t believe me. Idk what to do. I’m definitely going to wait to tell people after my first appointment. But it might have to be longer then that. What do y’all think I should do? Or how should I tell her?