There is something more elegant, about a 1911, in general, in my opinion. Even if the pistol remains concealed, I just feel “better-dressed,” with a 1911, in a high-end, well-crafted holster. Score one for the 1911, in this regard. Obviously, there is personal bias involved. 
Accuracy. I am, personally, much more accurate with a 1911, than with a G19. I am also much more accurate with a G17, than with a G19. I can get all of my skinny fingers onto the grip of a G19, but, at the rear of the grip, the “heel” of the G19’s grip does not reach the “heel bone” of my hand. This has always meant that a G19 tends to “float” more, in my grasp, than a pistol with a longer grip frame. For defending other persons, especially, consistent accuracy, over distance, really does matter. Score one, for the 1911, in this regard, but, in my personal case, NOT a “bobbed” 1911, if it does not firmly brace against the “heel bone” of my gun hand.
The holster type makes a difference, in what I would want to use. I would rather conceal a 1911, than a Glock, if using an inside-the-trousers rig. I have never liked carrying any wide-body pistol, or any railed pistol, inside my trousers. Score another, for the 1911.
Of course, all else being equal, I would rather carry OWB, which levels the playing field, in this regard.
If I anticipate having to store a pistol, inside a locked container, or secured with a locking cable, inside a vehicle, for an extended period of time, well, Glock, because a Glock is simpler, and less expensive, to replace. I do not like to leave any firearm, inside an unattended motor vehicle, but traveling can make this a temporary necessary evil, at some stops/destinations. The “family” and “vacation” part might result in other situations, activities, and circumstances that favor the Glock option. I do not know what the OP’s family likes to do, while traveling.
So, I lean toward the 1911 option. Elegant, civilized, and dressier, for the wedding. More accurate, over distance.
I must add a disclaimer about further bias. The “float,” that I mentioned, in the second paragraph, above, also means that shooting a G19 pistol, with my right hand being the weapon hand, became a painful experience, about the time I reached age 56, in 2017. As few as 80 rounds, of 115-grain FMJ can cause a week of swelling, and two weeks of pain. Full-height-grip 1911 and G17/G19x pistols remain “orthopedic” pistols, for now. I traded-away my three Gen4 G19 pistols, in 2020.
I do not overly concern myself with ammo capacity. One can add more 1911 mag pouches, to the belt, if that is an issue. I never liked carrying more than one spare Glock mag, on my belt, but find it no trouble to carry several of the relatively flatter 1911 mags.
Finally, of course, just carry the 1911, as “primary,” and the G19 as “secondary,” and be done with it.
Accuracy. I am, personally, much more accurate with a 1911, than with a G19. I am also much more accurate with a G17, than with a G19. I can get all of my skinny fingers onto the grip of a G19, but, at the rear of the grip, the “heel” of the G19’s grip does not reach the “heel bone” of my hand. This has always meant that a G19 tends to “float” more, in my grasp, than a pistol with a longer grip frame. For defending other persons, especially, consistent accuracy, over distance, really does matter. Score one, for the 1911, in this regard, but, in my personal case, NOT a “bobbed” 1911, if it does not firmly brace against the “heel bone” of my gun hand.
The holster type makes a difference, in what I would want to use. I would rather conceal a 1911, than a Glock, if using an inside-the-trousers rig. I have never liked carrying any wide-body pistol, or any railed pistol, inside my trousers. Score another, for the 1911.
Of course, all else being equal, I would rather carry OWB, which levels the playing field, in this regard.
If I anticipate having to store a pistol, inside a locked container, or secured with a locking cable, inside a vehicle, for an extended period of time, well, Glock, because a Glock is simpler, and less expensive, to replace. I do not like to leave any firearm, inside an unattended motor vehicle, but traveling can make this a temporary necessary evil, at some stops/destinations. The “family” and “vacation” part might result in other situations, activities, and circumstances that favor the Glock option. I do not know what the OP’s family likes to do, while traveling.
So, I lean toward the 1911 option. Elegant, civilized, and dressier, for the wedding. More accurate, over distance.
I must add a disclaimer about further bias. The “float,” that I mentioned, in the second paragraph, above, also means that shooting a G19 pistol, with my right hand being the weapon hand, became a painful experience, about the time I reached age 56, in 2017. As few as 80 rounds, of 115-grain FMJ can cause a week of swelling, and two weeks of pain. Full-height-grip 1911 and G17/G19x pistols remain “orthopedic” pistols, for now. I traded-away my three Gen4 G19 pistols, in 2020.
I do not overly concern myself with ammo capacity. One can add more 1911 mag pouches, to the belt, if that is an issue. I never liked carrying more than one spare Glock mag, on my belt, but find it no trouble to carry several of the relatively flatter 1911 mags.
Finally, of course, just carry the 1911, as “primary,” and the G19 as “secondary,” and be done with it.
