Tell her congrats from a fellow Marine.
MCT= Marine Combat Training it'll last about a month and she'll actually be at Camp Geiger which is attached to MCAS New River which is on the south side of Jacksonville, Camp Lejeune is on the north side. She'll be spending a lot of time sleeping in "worms" down at Camp Devildog a few miles south of the first fleet Barracks I ever stayed in lol. She'll be there at a decent time at least. During the summer it's unbearablely hot and humid and during the winter it's just wet and very cold. A lot like Paris Island
. For every one here all female recruits go to Paris Island for training no matter where they are at. Even if they live right out the front gate of MCRD San Diego. For males it goes along the lines of if you are west of the Mississippi you go to San Diego if you are east of the Mississippi you go to Paris Island.
If she is going to Missouri for training she'll almost for sure be going to Fort Leonard Wood (Fort Lost in the Woods). We send our Arty guys there also for training. Another potentially miserable place depending on time of the year
The Marine Corps has no bases in Missouri.
As for the cross country rides.......that's going to take some planning. We get 30 days a year off but it comes in 2.5 day a month parcels lol. In other words you can have 30 days of leave saved up to take if you don't take leave for a year. If she took 10 days leave from boot camp, like most people do, she'll already be negative in leave days. And then you have to have a command that will allow enough leave days to travel cross country. The commands I've been in usually have a 20 day limit on the number of days you can take. That makes taking long trips possible but takes time to build up that leave.