John if you can rename your post title
with something like "need help with Casita
Windows" you may get more help. In the meantime if there are weep holes in the windows track/frame. If they are plugged water may be backing up - try pushing some weed whacker cord through them to clear them.
If you use the search function on this site (use the bottom drop down option - google option) for best results you will probable find lots of info on the topic.
Looking at your profile photos it looks like the previous owner did use a lot of silicone and that historically doesnt fix much for long. It also looks like you may need new windows seals as well.
In the meantime there is an older thread called Casita Window Repair
that may help