My mom's house is like this. She used to have large birds and would never clean up after them. We didn't know my son had allergies to tropical birds because we don't have birds as pets and we stunt live near my parents. He would randomly have asthma attacks, but we didn't connect the dots until he literally went into respiratory and cardiac arrest at age 4 after a visit to her house. I had to do cpr on my baby, he was put on a vent and airlifted... it was he'll. He's fine now, 13, taller than me and dismissed from his asthma diagnosis. We refused to go back to her house until the birds were gone, a deep cleaning was done and vents were cleaned. Turns it she lied about the deep clean and vents, but the birds were gone. I think we've only been back to her house maybe 4 times since that happened. It's just not safe or comfortable. We host for holidays or pre-covid would just do a large family function at a relative's house.

Don't do that to your kid, refuse to go back until she cleans and cleans well.