Send an email to your cousin about the family reunion she's organising.

Hi Gem! I didn't know you were back from Paris, I'd written earlier, how was your holidays?
Your family meeting is the best idea I've heard since that gathering we spent at paintball battlefield, what a day!
I read the list and...are you sure about uncle Peter? Since they get divorced aunt Ana seems a bit gloomy.. Anyway, it's your reunion so it's up to you.
About the place your mum suggested i don't think of as a good option. It's a wonderful fishing island but, you know, granny's allergic to seafood. If you're stuck on that place make sure there'll be different plates. I was thinking about the day and s+September the 14th may suit all of us. I'll call Sam later and ask him if he can bring our parents and uncles on his car. Will your stepbrother come? He seemed kind last Christmas and Marc really got on with him.
Finally, Gem, it isn't clear at all in your email, are you thinking about a lunch or dinner reunion?

Drop me a line soon to put this all together.

Love, 

May.

Awesome English, keep working on it- just a few tiny errors! :)