Question Peg in center

Would/could a locking clip help prevent a seat from sliding? We have a 2012 with leather seats and when installing the seat in the middle it becomes too loose(2"-3") after one or two rides. I went to a tech and we installed it outboard with latch. Outboard is fine day to day but once a month or at least once every other month we have an aunt in the car and need to lean the front seat back and slide it a few inches toward the back seat which would be bracing the carseat. I could install behind the driver with latch seatbelt when we have an aunt in the car but would have to put it back behind passenger so that my dad could drive the car when needed.
The problem with the middle is there is a gap* between the driver back seat and middle seat. The pria fell into this gap and now the peg leans about 2" into the gap. So if I didn't lock the seat and just used a locking clip could that help any ? We have a few techs in the area but one never returned my email and one would just tell me to ff(he told me to once my dd was 1 even if she wasn't 20lbs and to booster at 3(which she almost is.) So I would like to see if this could help before taking it to one of the other techs or back to the one I just went to.

*this is what the gap looks like. I can't post any picture and don't have a way to link to the picture of the gap.
images.search.yahoo.com/images/view...∋=21&no=8&ts=&tab=organic&sigr=11nc72p81&sigb=13fe994tq&sigi=12l88ibd4&sigt=11ieo01hk&sign=11ieo01hk&.crumb=ia/4WVg8sW.&fr=onesearch&fr2=piv-web

Hi! Peg infant or convertible? With the 30/30, a locking clip is really helpful in many seatbelt installs. But I don't know if it would hero or not with a convertible (I'm guessing it's a convertible based on her age?) If it loosens over time, it sounds like you need more compression of the vehicle seat.

Your link doesn't work, can you tell me what vehicle? In general I'm not comfortable with the seat on a gap from split seats. Sometimes it can shift over enough to work, though.

This should work the pictures are at the bottom. If you look there is a small gap shown between the middle seat and driver back:

http://gearheadsmag.com/2012/07/16/cadillac-srx4/

It's a convertible. What I keep having is the driver side of the middle seat is compressing about 1.5" and the passenger side isn't compressing at all.

Oh yeah, that split would definitely cause a problem. And it looks narrow enough that just scooting likely won't do it. I have to agree that outboard is likely the best choice for a secure install.