A referral got me in the door, then the person who referred me went completely quiet. Is that normal?

Former coworker offered to refer me without me even asking, which felt like a genuinely good sign. Submitted my info through her, got an interview scheduled within a week, felt momentum for the first time in a while.

Then nothing — no response to two follow-up messages, no idea if she's just busy or if something changed. The process itself is still moving forward on the recruiter side, so it's not like it fell through.

I just don't know whether to keep updating her, assume she's checked out of it entirely, or if this is a normal amount of silence once the referral's already done its job and I'm reading too much into it.