The correct phrase is 'ask after' when inquiring about someone's well-being or situation. 'Ask after' means to inquire about how someone is doing or what has happened to them. 'Ask before' doesn't make sense in this context.
Ask after someone is an idiom meaning to inquire about a person's wellbeing (e.g., asking how they're doing), which fits the context of phoning home to check on family. Ask before, ask towards, and ask from aren't standard idiomatic phrasings for this meaning.