Mailmerge

I am working on a fundraiser project & have ~4500 rows of data (name, address, pledge, paid, etc.) I am going to use this info for a mailmerge and am would like to minimize my work if possible. Example: sending out thank you letters and I have 1 sponsor that may have sponsored 4 students. I want to send only 1 letter and include the 4 names of the students within the letter instead of sending 4 individual letters. Is there a way to automate this process?

Thanks for your help.

I haven't tried it but it looks like it could do the job.
And it says: FREE
//Ola