Brief Answer:
Long incubation period

Detailed Answer:
Dear Ma'am,

I have gone through your question and I understand your concerns but unfortunately infectious mononucleosis has a long incubation period that can last up to 6-8 months before producing any symptoms and most patients can spread symptoms during this period.

infection is mostly transmitted through saliva either by direct contact or airborne droplets which is less unlikely .. infection can also spread through sexual contact and blood.

As for your pregnant daughter , reinfection cannot occur as once she got infected once the virus remains dormant in her body and it usually has no dangerous effect on the mother or child .

For the other kids and elderly person present in the party , it is unlikely to get infected without direct contact of saliva but still there is a small risk of infection.

However, infectious mononucleosis is usually a mild disease that can present by :
a fever
a sore throat
swollen lymph glands in your neck and armpits
a headache
fatigue
muscle weakness
swollen tonsils
night sweats
The symptoms are easily treated and self limited without any complications except in rare cases where spleen or liver enlargement occur..

I hope I answered your question

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Brief Answer:
Yes, you're right

Detailed Answer:
Dear Ma'am, Hello again..
Thank you for correcting me,

Yes, I meant less likely... However, your first daughter needs to cover her mouth and nose, avoid sharing any utensils with him and also avoid sexual intercourse to avoid getting infected if her test came back negative...

I hope you find this helpful.
Regards

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