Hi Diananil,
Elaine, Jackie, Elaine and Reid welcome you to the DLP DIS board
We are a friendly bunch here so please join in on any other thread or if you have a number of questions then just start a new thread for each
If you have not had a look yet, DLP posting rules are here
http://www.disboards.com/showthread.php?t=1477038,
DIS posting guidelines can be found here
http://www.wdwinfo.com/guidelines.htm
have you looked on travelrepublic, expedia, alpharooms for
Disneyland Paris hotels (you'll get a list of onsite and offsite hotels, hotels in Val d'Europe and Bussy St Georges are local and convenient for DLP by train every 5 minutes or so all through the day and evening).
Ibis, Etap, Premier Classe have hotels nearby too - they have their own websites to get availability/prices.
Is your brothers room onsite at maximum occupancy? If not, and you intend buying an annual pass or park ticket yourself, you can be added to your brother's room details when you arrive, at check in. You will only have local taxes to pay (around 2 euros per nights stay).