Plaster Damage Repair

Hi, I'm new to the site and looking for any help available. I've returned home from college and my mom has alot of work that needs to be done around her home. But one issue seems like it's more pressing than others... The house was built in 1963 and has plaster walls over concrete block. Around the bedroom window, I noticed paint peeling and plaster flaking off. The more I looked around the window, the more I noticed the plaster sort of "bubbling" up in places. There are also two new cracks (new to me, anyway) beneath the window.

Here are photos of the damage.

If anyone has advice for me, it'd be great. I'd really just like to know what could have caused this (water damage?) And what I should do about getting help to get it fixed. Any advice?