Not directly about foster parents - but I love Chad's story by Changing Minds (can find it on Vimeo or YouTube). It shows a young man coming back to his community after 8 years (hard to know the exact ages) - but he speaks about his high school graduation. He clearly went through some trauma and is able to process/regulate what he experienced.
A companion video about Unique - a female story of overcoming - from Changing Minds is good as well.
They are both under or about five minutes.
The ReMoved video is powerful - but the second part is where you see resilience, so it is long (over 12 minutes for the first part and 22 or so minutes for part 2).
Remembering Trauma Official Film is also a good one, but it is about 16 minutes (2 of them are credits) and it kind of gets into resilience late (about the 10:30 minute mark).
I’d love to hear what others are using – what other suggestions you get – and what you go with.