"Keep you chin up" is something that you say to someone in a difficult situation in order to encourage them to be brave and to try not to be sad.
This little goat was heavily pregnant, and you'll be glad to know she kept her chin up and had three, healthy kids.
THIS IS NO HELP AT ALL WHEN YOU ARE TRYING TO FIND THE MEANING TRY AND MAKE AN ACUAL THING THAT HELPS STUDENTS AND NOT CONFUSES THEM YOU SUCK
Thanks for pointing out, and in such a charming way, that I'd made a mistake on the title.