Quick Check Results (if you have follow-up questions, send me a message through my contact page)
Dobby HouseElf: Your kids are in the right seats for their age/height/weight, and your installation methods look good for these seating positions. Just be sure that you are harnessing them properly according to your manual, and keep in mind that your little one will likely outgrow the seat by height long before reaching the weight limit of the seat. For your older kid, that seatbelt install will mean you won't have to make a switch when he/she reaches the lower anchor limit of the seat. Just be sure that the seatbelt is locked. You've got plenty of rear facing time left in that seat! One last thing...as I see you drive a pacifica, I strongly recommend joining the Chrysler Pacifica Facebook group if you aren't in there already. There are some challenges to installing car seats in this vehicle and it may be helpful down the road!
Mama2016: You're looking good! Your kiddo still has a while before hitting the 49" height limit of the seat, but if you intend to keep him or her harnessed as long as possible, make sure the harness is adjusted so it's coming out at or slightly above the shoulders. Once the shoulders start to go above the harness at the highest position, it is outgrown even if that 49" isn't hit (things can be torso-dependent!) I'm glad to see you have the seat installed with the seatbelt as you've just exceeded the 45lb weight limit for a Lower anchor install, but good for keeping the seat tethered. Make sure the seat doesn't move more than a inch side to side or front to back. I recommend keeping kids in a harnessed seat until they're at least 5, but you want to make sure that they're mature enough to sit properly 100% of the time, even while sleeping. It may not be a time for a switch until 6 or later.
YankeeP: You do have a few corrections to make. First off, I'm thinking that "145" for height is a typo because it doesn't work for inches or centimeters :). Assuming you mean 45", your child is within the height and weight limits for forward facing in this seat. First needed FIX: your seat cannot be installed with both LATCH and seatbelt. Britax. like most car seat manufacturers want you to use one or the other--not both, and in your case, you must install by seatbelt because lower anchor use must be discontinued when your child hits 40 lbs in a forward facing install of this seat. (I am also assuming that this is a Marathon Clicktight based on the manufacture date, but if it is an older, non click-tight seat, the weight lim it is 45, so it's still a good time to switch.) Britax actually prefers a seatbelt install with their clicktights because it is so simple to use. Second needed FIX: All forward facing harnessed seats should be tethered. This reduces forward head movement in crash by up to 6". Without it, there's more chance of the child hitting the seat in front of them. The tether is tucked into a compartment on the back of the seat. You didn't specify position, but if you're using the center seat, your tether anchor is on the ceiling under a plastic flap close to the back hatch. On the outboard seats they are on the back of the seat. Your vehicle owners manual has pictures, but you can route the two pieces of the webbing around the raised headrest if that works better than going between the bars.
Belle Swan: Overall, things look good. I do consider 5 to be a minimum for booster seat use, so make sure your child is mature enough to sit properly 100% of the time...even when sleeping. Be sure to adjust the headrest of the turbobooster as needed; the red belt guide should be at or above the shoulders. Also see my previous post about turbobooster screws. If yours needs them and they're missing, call Graco for replacements. For the E2F, make sure the harnesses are at or below the shoulders and not above. Keep rear facing as long as you can and pay attention to the seat's recline requirements if you end up turning forward before 40 lbs.
Reba: Be aware that the Nautilus requires a seatbelt install once the child hits 45 lbs (dressed, shoes, full stomach), so you may want to do that soon. You will continue to use the top tether.
Beyonce: Graco gives the option of using the tether when the nautilus is in booster mode. It's not required, but as you have a tether anchor in that seating position you can use it to give the seat a bit more security when it isn't occupied (note, it's always a good idea to buckle the seat in with the seatbelt when it's not occupied, to keep it from being a projectile in a crash). Also note, your vehicle doesn't allow the 3rd row to be folded flat when there is a car seat back there.
Wima Butfit: You have a tall one! Remember that the keyfit 30 has a 30 lb weight AND 30" height limit, so once the baby hits 30 inches the seat is outgrown even if well below the weight limit. If baby has a long torso, it may be outgrown before 30". Make sure there is at least 1" between the top of baby's head and the top of the plastic shell of the seat. If there is less, the seat is outgrown even before 30". It will then be time to move to a rear facing convertible seat.
Tired Mom: Assuming you're still using the Tranzitions in harness mode, it's time to switch from LATCH to a seatbelt install! The tranzitions lower anchors max out at 45 lbs. If you have trouble getting a tight (less than 1" movement side to side and front to back) with the seatbelt, try reclining the vehicle seat a notch or two before you install. Get it tight, then bring the seat back up to its regular position. The seat has a 65 lb weight limit, but it has a 49" height limit for the harness. Once kid hits 49". or when shoulders are above the harness slot at the heights position, it will be time to switch to booster mode.
Dobby HouseElf: Your kids are in the right seats for their age/height/weight, and your installation methods look good for these seating positions. Just be sure that you are harnessing them properly according to your manual, and keep in mind that your little one will likely outgrow the seat by height long before reaching the weight limit of the seat. For your older kid, that seatbelt install will mean you won't have to make a switch when he/she reaches the lower anchor limit of the seat. Just be sure that the seatbelt is locked. You've got plenty of rear facing time left in that seat! One last thing...as I see you drive a pacifica, I strongly recommend joining the Chrysler Pacifica Facebook group if you aren't in there already. There are some challenges to installing car seats in this vehicle and it may be helpful down the road!
Mama2016: You're looking good! Your kiddo still has a while before hitting the 49" height limit of the seat, but if you intend to keep him or her harnessed as long as possible, make sure the harness is adjusted so it's coming out at or slightly above the shoulders. Once the shoulders start to go above the harness at the highest position, it is outgrown even if that 49" isn't hit (things can be torso-dependent!) I'm glad to see you have the seat installed with the seatbelt as you've just exceeded the 45lb weight limit for a Lower anchor install, but good for keeping the seat tethered. Make sure the seat doesn't move more than a inch side to side or front to back. I recommend keeping kids in a harnessed seat until they're at least 5, but you want to make sure that they're mature enough to sit properly 100% of the time, even while sleeping. It may not be a time for a switch until 6 or later.
YankeeP: You do have a few corrections to make. First off, I'm thinking that "145" for height is a typo because it doesn't work for inches or centimeters :). Assuming you mean 45", your child is within the height and weight limits for forward facing in this seat. First needed FIX: your seat cannot be installed with both LATCH and seatbelt. Britax. like most car seat manufacturers want you to use one or the other--not both, and in your case, you must install by seatbelt because lower anchor use must be discontinued when your child hits 40 lbs in a forward facing install of this seat. (I am also assuming that this is a Marathon Clicktight based on the manufacture date, but if it is an older, non click-tight seat, the weight lim it is 45, so it's still a good time to switch.) Britax actually prefers a seatbelt install with their clicktights because it is so simple to use. Second needed FIX: All forward facing harnessed seats should be tethered. This reduces forward head movement in crash by up to 6". Without it, there's more chance of the child hitting the seat in front of them. The tether is tucked into a compartment on the back of the seat. You didn't specify position, but if you're using the center seat, your tether anchor is on the ceiling under a plastic flap close to the back hatch. On the outboard seats they are on the back of the seat. Your vehicle owners manual has pictures, but you can route the two pieces of the webbing around the raised headrest if that works better than going between the bars.
Belle Swan: Overall, things look good. I do consider 5 to be a minimum for booster seat use, so make sure your child is mature enough to sit properly 100% of the time...even when sleeping. Be sure to adjust the headrest of the turbobooster as needed; the red belt guide should be at or above the shoulders. Also see my previous post about turbobooster screws. If yours needs them and they're missing, call Graco for replacements. For the E2F, make sure the harnesses are at or below the shoulders and not above. Keep rear facing as long as you can and pay attention to the seat's recline requirements if you end up turning forward before 40 lbs.
Reba: Be aware that the Nautilus requires a seatbelt install once the child hits 45 lbs (dressed, shoes, full stomach), so you may want to do that soon. You will continue to use the top tether.
Beyonce: Graco gives the option of using the tether when the nautilus is in booster mode. It's not required, but as you have a tether anchor in that seating position you can use it to give the seat a bit more security when it isn't occupied (note, it's always a good idea to buckle the seat in with the seatbelt when it's not occupied, to keep it from being a projectile in a crash). Also note, your vehicle doesn't allow the 3rd row to be folded flat when there is a car seat back there.
Wima Butfit: You have a tall one! Remember that the keyfit 30 has a 30 lb weight AND 30" height limit, so once the baby hits 30 inches the seat is outgrown even if well below the weight limit. If baby has a long torso, it may be outgrown before 30". Make sure there is at least 1" between the top of baby's head and the top of the plastic shell of the seat. If there is less, the seat is outgrown even before 30". It will then be time to move to a rear facing convertible seat.
Tired Mom: Assuming you're still using the Tranzitions in harness mode, it's time to switch from LATCH to a seatbelt install! The tranzitions lower anchors max out at 45 lbs. If you have trouble getting a tight (less than 1" movement side to side and front to back) with the seatbelt, try reclining the vehicle seat a notch or two before you install. Get it tight, then bring the seat back up to its regular position. The seat has a 65 lb weight limit, but it has a 49" height limit for the harness. Once kid hits 49". or when shoulders are above the harness slot at the heights position, it will be time to switch to booster mode.