Party for children.

I have a friend I met in medical school. In addition to her usual work, a doctor like myself, she is also a missionary. Yesterday evening she arranged for an international party at an orphanage. Her friends and I helped her to prepare it. We all cooked a famous national dish from our homeland.

Sorry I changed a lot, but I wanted to show more common words used. Hope I didn't change any meanings for you! 

Party for children.

I have a friend. We studied together in the medical school. In addition to her usual work (she is also a doctor like me) she is a missionary.

Yesterday evening she arranged for an orphanage where orphans live international party.

Yesterday evening, she arranged an international party for an orphanage ("where orphans live" is not needed since this is the definition of orphanage) .

Her friends help to prepare it. We cooked a meal, depending on the country which we come from.

Her friends helped to prepare it. We cooked a meal, depending on the country which we came from.

Party for children.

I have a friend. We studied together in medical school. In addition to her usual work (she is a doctor like me), she is a missionary. Yesterday evening, she arranged an international party for an orphanage. Her friends helped prepare it. We cooked a meal, depending on the country which we came from.