Surprise announcement on sisters bday

Cin • 1st x mommy | Cali | 29

Need advise! My older sisters birthday is coming up, she has no kids by choice and was thinking of giving her a regular birthday gift along with a surprise gift about her being promoted to aunty! I am debating if I should give her the pregnancy surprise gift on her birthday or wait so I don’t steal her shine on her birthday... we are close so not sure how she’ll handle it. Share your thoughts please ☺️