A family tent (i.e. something like a Vango Omega 600XL) and some military BCB sleeping cots could easily be carried in an SUV.

http://www.youtube.com/watch?v=6iQhcQ7_p-c

http://www.youtube.com/watch?v=_dPsRW0zjrs (Use with an appropriate Thermarest or Multimat inflatable mat for cold weather bug out)

A lifesaver Jerrycan and a couple of 20l NATO water Jerry cans would provide around 60 Litres or nearly 16 US Gallons of water for 1 gallon per person per day. Enough for 7 days.

http://www.youtube.com/watch?v=zWjZ0i94eTQ

http://www.youtube.com/watch?v=mhn8r7W0YLk

A multifuel stove (one which can also take Gas Cartridges such as 4 season mix for convenience inside the tent 2-3 500gm cartridges should easily last more than 1 week) i.e. a Primus Omnifuel Himalaya Stove, which can also use unleaded petrol outside the tent.

http://www.youtube.com/watch?v=Tdja7UCIt0Y

Add a couple of 20 litre Jerry Cans for additional Petrol. If you can get the NATO spec Explo-Safe jerry cans together with the spout.

http://www.jerrycans.co.uk/explo-safe-jerry-cans-30-c.asp

These may extend your vehicle range from 100-200 miles for the additional 10+ US gallons of fuel.

Food for 1 week at 3000 Kcal per person per day using French RCIR rations or something similar would weigh around 21Kg for 14 ration packs. (excluding the baby food of course). You could go lighter (save 50% weight) with freeze dried but this would be dependent on available water available if water is heavily contaminated.

http://www.youtube.com/watch?v=62Ykn5daKng

Again various tools are a requirement as well such as an entrenching tool or small spade, axe, saw etc.

Total Additional weight to your BOBs in the SUV vehicle would be around 150-160 Kg

You may also consider using a large Camo Net enough to cover both the SUV vehicle and Tent when parked up out the way.

Has anyone else considered using a military helmet and plate carrier when bugging out by vehicle? (not so much of a concern in the UK)