Sandra Cirera-García Jul 16, 2020:

Sounds good and you're welcome!

Gabriela Hernandez (asker) Jul 16, 2020:

Yes! I agree! I kept researching and I found what a sibling cake is! :-)

It is a service they offer at The Woman's Hospital of Texas, such a nice
gesture! :-)

To help celebrate your new baby with brothers or sisters, we are happy to
provide a sibling cake the day before discharge or the morning of the
discharge. To order a sibling cake, please call extension 3663. Delivery
times are 10:30 a.m. or 3:30 p.m.

https://womanshospital.com/service/postpartum#:~:text=Siblin...


So, my proposed translation would be "pastel para celebrar la llegada del
hermanito"
Thank you Sandra for your input!

Sandra Cirera-García Jul 16, 2020:

From a hospital website: "At Your Request™ Room Service Dining allows patients and their guests to order food anytime between 6:30 a.m. and 6:30 p.m. An operator will take your order, and in 45 minutes, food will be delivered to your room. Guest trays are available and can be purchased in the café or by phone at ext. 3663. You may also order siblings' cakes to help brothers and sisters welcome their new family member."

Looks like it's a cake that can be ordered from the hospital catering for a new baby's sibling/s, to help them celebrate the new arrival.