I have no issues with taking family members to the ED with me, within reason. Here, we're strongly encouraged to take them if they wish to come. Now, understandably there are family, and/ or friends that I would not want coming with me for several types of reasons; theses people are often "verbally judo-d" into taking their own vehicle, and/ or meeting up with said patient later at the ED.
As a parent, if I wished to ride with my child regardless of their age, you're damn right I would not be happy with someone telling me I can't, as would my wife. I think over the years I have begun to understand this firsthand. So, for me the average well-meaning family member who means no harm, and may be able to provide further history on the way to the ED (gotta love the "cubby holes") I take with me. If it's a small, scared child I let mom in back, and if anything I am leery of the patient's parent who
doesn't want to ride along, especially if they don't have other children to tend to at the time of the call. I do miss the days when we would slap baby of mom's lap, then on the gurney at times (talk about liability) as it made some things easier; clearly this was extremely unsafe though.
This is just my take, and reasoning as to why I would let a presumably reliable family/ friend ride in with us without hesitation. Obviously, they're belted in, but I guess I feel like who am I to tell them no? They're concerned, and again as long as they're fairly level headed they're welcomed to join in.
To add to this, with critical calls, on scene or even en route I was taught by one of my paramedic proctors to invite them in if they so wish, which I do. If they're genuinely calm, and concerned and want to know what, and why we are doing what we are doing, why not allow them to see, and/ or know what it is their family member is being put through? I clump this into the "explaining the procedure" category; sometimes family wants to know, which is fine. This is no dig at
@DesertMedic66's style, it's just what I have been taught, coupled what I have learned over the years from a "concerned family member's" point of view when my child/ wife is ill, and taken to the ED, or U/C for treatment. I have yet to take an ambulance, though.