20 and pregnant w/second child

Soooo my boyfriend and I found out I was pregnant with our second child and we are so excited. We have been together for 4 years we have our own place, great stable jobs and we are planning on getting married in the next two years. I am nervous because I'm not sure how to tell my mom. She had me when she was 15 years old and when she found out I was pregnant with my dd at 18 she was angry and told me to get an abortion. Although she loves my daughter now, I'm scared what she will say when I tell her I am pregnant again. I have no clue how to approach her. What do you think would be the easiest way to tell her?