Name change, as I'm not sure if I have family on here. Long story short, my brother and his wife have just had their first baby. Due to Covid, nobody was able to see her in person, although DB/SIL almost allowed SIL's parents to fly in from across the country to visit for the birth. We all live in the States, and the pandemic is very bad here. Ultimately, they decided against it due to this, and the baby not having an immune defense yet.
Now, with DN just two months old, they've booked a rental truck with a small trailer hitched on the back and are planning to drive in a few weeks across the entire USA from one hotspot to another (where they live is currently on lockdown, but they're still planning to leave), to bring their little one "for a visit." There is no medical or safety need for this, and it isn't for work. They'll be planning to visit with multiple families while they're here, including many people in at-risk groups. Yes, they will be breaching the stay at home order, but their defense is that it's not technically illegal (or at least won't be enforced as such).
Because all the family (including us) also live in a hot spot, they're asking family to "quarantine" for six to ten days beforehand and for the duration of their visit (two weeks), and to pay for a Covid test so they can hold the baby. This means that several people in SIL's family (as well as mine) have to stay home from work for several weeks.
SIL's younger sister, who works in retail, could lose her job over such a long absence; while SIL has expressed concern over this possibility, she's asked it all the same. Her younger sister still lives with her parents, and she wants them to see the baby: so they and her sister have to quarantine together. SIL's father has had some major health events this year and used up all his leave/work from home time. He's concerned he won't be able to quarantine as long as she wants, so SIL has just shortened the quarantine time they're asking for to six to ten days, from the CDC recommended 14.
When my brother called to tell us their plans, I let them know we wouldn't be able to see them during their visit. We have a toddler and a preschool aged child, and I am terrified of accidentally giving something to DN, as well as catching something from DB/SIL from their trip across the country from one hotspot to another. They say they'll be "quarantining" in their rented trailer, but with stops for gas/food/etc. in various hot spots along the way, I'm not sure how it's possible to do a full quarantine. My DH's health history is sketchy, so I'm not comfortable putting him at risk either. While they were fine with our decision, the rest of the family thinks we're unreasonable for declining.
We have also canceled holiday plans with the rest of the family. I'm gutted, but we do have to be careful and numbers in our state have been skyrocketing upwards. Added to our family telling us that breaching government guidelines is "safe enough", we'd rather wait to gather until the stakes aren't so high for us. I know they disagree with our decision, but if we catch it the consequences could be very bad. They're obviously upset about all this, and blame us. I feel awful, but we didn't create this situation; added to that, the family aren't being as safe as we need for our situation, so I don't see how we could manage a get-together and trust them to social distance/wear masks, etc. AIBU?