I know the onsite hotels normally do stuff for major holidays. However, they don't post the menus online (or normally even mention it) until it is almost the next holiday that they have something special going on.
Also, don't expect the Universal's site to update for Easter. They might, but I doubt it. The best thing to do is to check the Loews Hotel website. They have all the menus for all three onsite hotels listed here. They also have an area for holiday menus, but right now it simply says to check back later. In Dec. it had the Christmas menu here, so it does get updated.
Also, if you don't see anything updated and you are about a week or two away, you can call the hotel and ask if they have anything planned. Normally these "Holiday event menus" can be expensive, so be sure to check on the price before going.