Anyone have any input?

So my sister just had a baby a few days ago and she failed both of her hearing test at hospital and she does not react to any noise like if you clap or drop somthing. She has a specialist appointment in a few weeks. Is it possible her ears could be clogged?? Being deaf dont run in any of the families and she has a super healthy pregnancy just curious on how high the chances are that she is deaf🤔 which if she is that's totally fine, my learning sign language journey will begin!!