Hi
Will try to make this setup but will need to know if it will Work.

To understand the schematic.
Supply is there allways.
When i put 12v on the "12-14v input 10mA max" wire both mosfet should get power out to "Out 12-14 V 10A Load" wire.
When i just put 12v on the "12-14v input 10A max" wire, only the one mosfet should set power out to "Out 12-14V 10A Load" wire.

Will it Work, or am i totaly wrong,
Have attached both datasheet,

 

It should work despite the fact that you are using wrong symbol for a P-MOS. Also you can increase R38 and R40 to 10KΩ.
And do not forget about power dissipation in P-MOS. PD = Id^2*Rds(on) = 10A^2 * 0.07Ω = 7W so you need a big hest-sink or new PMOS with lower Rds(on).